N: Skipping acquire of configured file 'main/binary-i386/Packages' as repository 'http://prerelease.keybase.io/deb stable InRelease' doesn't support architecture 'i386'

sudo apt update gives me the following message:

$ sudo apt update
...
N: Skipping acquire of configured file 'main/binary-i386/Packages' as repository 'http://prerelease.keybase.io/deb stable InRelease' doesnt support architecture 'i386'
...

# ADDITIONAL INFO
$ cat /etc/apt/sources.list.d/keybase.list
deb [signed-by=/usr/share/keyrings/keybase-keyring.gpg] http://prerelease.keybase.io/deb stable main

$ gpg --show-keys /usr/share/keyrings/keybase-keyring.gpg
pub   rsa4096 2013-11-19 [SC] [expires: 2027-11-11]
      222B85B0F90BE2D24CFEB93F47484E50656D16C7
uid                      Keybase.io Code Signing (v1) <code@keybase.io>
sub   rsa4096 2013-11-19 [E] [expires: 2027-11-11]

$ uname -a
Linux REDACTED 5.19.0-50-generic #50-Ubuntu SMP PREEMPT_DYNAMIC Mon Jul 10 18:24:29 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

$ lsb_release -a
LSB Version:	core-11.1.0ubuntu4-noarch:printing-11.1.0ubuntu4-noarch:security-11.1.0ubuntu4-noarch
Distributor ID:	Ubuntu
Description:	Ubuntu 22.04.3 LTS
Release:	22.04
Codename:	jamm

$ keybase version
Client:  6.2.2-20230726175256+4464bfb32d
Service: 6.2.2-20230726175256+4464bfb32d

$ sudo apt install keybase
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
keybase is already the newest version (6.2.2-20230726175256.4464bfb32d).
0 upgraded, 0 newly installed, 0 to remove and 2 not upgraded.

Apart from that message keybase seems to be working fine as always.

Start by reproducing sudo apt update on Ubuntu 22.04 using the source configuration in /etc/apt/sources.list.d/keybase.list, and compare it with the repository's published architecture metadata. Done means the Keybase repository can be used without the reported i386 warning while installation and upgrades continue to work.