Add Croatian (hr) language to the translation project

### Description

I'd like to translate the app into Croatian (hr), but I myself can't add it to the list of locales in the translation project.

### Screenshots or screen recording

_No response_

### Did you search for existing list?

- [x] I have searched for existing issues.

Start by locating the translation project's list of supported locales in the Pocket Casts Android repository. Add Croatian with the locale code hr, then verify that the translation project recognizes it as an available language.

Written by the indexing model from the issue text.