Only check changed files

[samrobbins85]

I don't know if it is possible with GitHub actions, but it would be great if you could only check the files changed in a commit/PR

[joaojhgs]

This right here should definitely be a feature, the original review dog action already has a flag to deal with that called filter_mode: 'diff_context'.

I think it's essential to make this action work with big translation files.