ci: allow multi submission

[ReenigneArcher]

Double check these details before you open a PR

• PR does not match another non-stale PR currently opened

Features

This PR allows multi submission edits in a single PR, as discussed in #2270.

This PR closes NONE

Notes

I have tested this against the same branch that creates #2270 in my local fork. This is the resulting comment: ReenigneArcher#1 (comment). All of the comments are valid issues, so I believe this is working as expected.

Note, that somewhere in the code empty strings are getting added to the error list. I don't believe this is anything from my changes, but I have just removed the empties using the following line.

err_msg = list(filter(None, err_msg)) # remove empty strings from err_msg

Some trailing whitespace was also automatically removed from lines in modified files.

@Snailedlt FYI

[Snailedlt]

Great!
I'll see if I can take a look at the PR this weekend

[Snailedlt]

This looks very good!
However I think we might get issues with the release script, since that also builds icons based on the PR title.
I might be wrong here, but iirc that's a different script, which will also need to be refactored.

To test out if this works with the release script(s), you can go through the release guide on your fork, and see if you get any errors, and if every step executes as expected.

If you find any ways to make the release process simpler, please feel free to adjust it as you see fit :)

[ReenigneArcher]

However I think we might get issues with the release script, since that also builds icons based on the PR title.

Thanks for the review. I'll dig into that in the next few days and report back.