Install scriptlet fails for rpm in Fish shell on Fedora 31

I have previously installed Keybase using the 64-bit RPM package without any problems.

However the new update generates a stack of script errors.

I have my user account sett to use Fish Shell, I am installing the package using `sudo dnf install`

It's not clear what this script is trying to do, but it caused my shell to behave oddly (displaying an echoed character for the return key) so I removed the package until this can be fixed.

```fish
> sudo dnf install https://prerelease.keybase.io/keybase_amd64.rpm
[sudo] password for username:
keybase 6.5 kB/s | 3.3 kB 00:00
keybase_amd64.rpm 14 MB/s | 156 MB 00:11
Dependencies resolved.
==============================================================================================================================================================================================================================================
Package Architecture Version Repository Size
==============================================================================================================================================================================================================================================
Installing:
keybase x86_64 5.3.0.20200310205642.4f2689009b-1 @commandline 156 M

Transaction Summary
==============================================================================================================================================================================================================================================
Install 1 Package

Total size: 156 M
Installed size: 434 M
Is this ok [y/N]: y
Downloading Packages:
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
Preparing : 1/1
Installing : keybase-5.3.0.20200310205642.4f2689009b-1.x86_64 1/1
Running scriptlet: keybase-5.3.0.20200310205642.4f2689009b-1.x86_64 1/1
Redirecting to /bin/systemctl start atd.service
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
Autorestarting Keybase via systemd for daganm.
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
/usr/share/Modules/init/fish: line 2: set: -g: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]
/usr/share/Modules/init/fish: line 6: syntax error near unexpected token `('
/usr/share/Modules/init/fish: line 6: `for _mlv in (string split ' ' $MODULES_RUN_QUARANTINE)'
sed: can't read /usr/share/Modules/init/.modulespath: No such file or directory
Restarted existing root redirector via systemd.

Verifying : keybase-5.3.0.20200310205642.4f2689009b-1.x86_64 1/1

Installed:
keybase-5.3.0.20200310205642.4f2689009b-1.x86_64

Complete!
```

Start by reproducing the RPM installation with `sudo dnf install` on Fedora 31 while using Fish, then inspect the install scriptlet output and `/usr/share/Modules/init/fish`. Done means the package installs without the repeated Fish and missing `.modulespath` errors and the shell remains usable afterward.

Written by the indexing model from the issue text.