fix translations_path

[LeXofLeviafan]

The translations_path constructor parameter appears to have never actually worked with flask-babel, because flask_babel.Domain does not have a get_translations_path() method to override (unlike flask-babelex).

[samuelhwilliams]

Thank you - good catch. We definitely need some better tests around some of these areas - could you raise an issue to track that (and/or if you're willing to write some tests around babel, that would be very useful) 🙏

see comment

[samuelhwilliams]

Would you mind also adding a line to docs/changelog.rst recording this bug fix?

Along the lines of:

2.0.0a1
-------

Fixes:

* Fix `translations_path` attribute when Flask-Admin is used with Flask-Babel.

[LeXofLeviafan]

I've added a test for translations_path… though it's rather low-level 😅 (The upside is that it doesn't require doing actual environment setup as it only checks whether the specified directory gets used when building the translations cache.)

As for raising an issue – I suspect you'd know how to word it better (and what else needs to be tested) as you're more familiar with the codebase 🤔