gh-130197: Fix (and test) option in pygettext

[StanFromIreland]

This also required some updating of the snapshot testing logic to handle multiple files. This function should get more testing and I will come back to this once I complete more research. For now I fixed (and tested) what was implemented.

• Issue: pygettext: Improve test coverage #130197

[StanFromIreland]

Request @tomasr8 @serhiy-storchaka

[StanFromIreland]

Also, can we rename it to skip-docstrings since it just make so much more sense. (There so be no backwards compatibility concerns since the current option dosen't work anyway)

edit: Tommorow I’ll update the PR renaming it to exclude-docstrings

edit2: It has now been renamed to exclude-docstrings. This is much clearer (and consistent) that the option needs to be passed something, and is less conflicting with --docstrings.

[tomasr8]

ok if we're gonna go with fnmatch, I'd also update the docs for the option to mention that fnmatch-style patterns are supported. I'd also add more tests for wildcards and directories.

[StanFromIreland]

ok if we're gonna go with fnmatch, I'd also update the docs for the option to mention that fnmatch-style patterns are supported. I'd also add more tests for wildcards and directories.

Do we want this though? I guess we can, but should we.