Update GA to create POT on specific branch pushes

[afragen]

I have checked the following:

• I've searched existing issues and found nothing related to my issue.

Describe the feature you want to add

Update generate-pot.yml to run on push to main and translations branches.

Will remove translations branch and replace with git flow branch after merge and once git flow defined here.

Fixes #197

Mockups or Images of the feature

n/a

[afragen]

Is the plan for development to use some sort of git flow process? I ask because if main is the release branch it would make sense to create a develop branch to make PRs against and feature and/or bugfix branches. develop would be the only branch that merges to main and this at the time of releasing a new tagged version.

Should something like the above be the process it makes sense to generate a new POT file on push to main.