Installing in Firefox (...) failed on Fedora 37

## Environment

* Operating system (including version): Fedora 37
* mkcert version (from `mkcert -version`): 1.4.4
* Server (where the certificate is loaded): N/A
* Client (e.g. browser, CLI tool, or script): N/A

## What you did

`mkcert -install`

## What went wrong

The local CA is correctly installed in the system store, but it's not possible to install for the browser.

```
The local CA is now installed in the system trust store! ⚡️
Installing in Firefox and/or Chrome/Chromium failed. Please report the issue with details about your environment at https://github.com/FiloSottile/mkcert/issues/new 👎
Note that if you never started Firefox and/or Chrome/Chromium, you need to do that at least once.
```

## Some investigation

After digging a bit into the code and verifyng the `~/.pki/nssdb/cert9.db` NSS db exists, I tried running
```
certutil -L -d sql:/home/mbolis/.pki/nssdb/cert9.db
```
and got an error
```
certutil: function failed: SEC_ERROR_BAD_DATABASE: security library: bad database.
```

At this point I tried
```
certutil -L -d /home/mbolis/.pki/nssdb
```
and indeed the result is positive. It actually looks like the "mkcert development CA" was in fact created.

Hoe this helps