[spaceship] Adding three missing beta testers/groups methods

[gsavit]

Checklist

• I've run bundle exec rspec from the root directory to see all new and existing tests pass
• I've followed the fastlane code style and run bundle exec rubocop -a to ensure the code style is valid
• I've read the Contribution Guidelines
• I've updated the documentation if necessary.

Motivation and Context

Implementing the following missing TestFlight endpoints for beta testers/groups related functionality:

Add testers to build
Remove testers from build
Remove groups from build

[joshdholtz]

This is great! Thanks for adding these 😊 Just a few suggestions about the order of method parameters so we can keep things consistent

[gsavit]

This is great! Thanks for adding these 😊 Just a few suggestions about the order of method parameters so we can keep things consistent

For sure, thanks for the review Josh! I wasn't too sure what to do with the ordering as it seemed to already vary within the file 😅

[kerrmarin-lvmh]

This is awesome! And I believe it's a first step towards fixing #17899 ?

[gsavit]

This is awesome! And I believe it's a first step towards fixing #17899 ?

Thanks! I don't quite think this has anything to do with that other issue, unless I'm missing something? (Incidentally, separately, I've been poking around looking for betaTesterMetrics as well and noticing it's not actually available in ASC API, maybe related to that issue...)

[joshdholtz]

This looks good to me! Thank you so much for this PR. Really appreciate it 🥰

[fastlane-bot]

Hey @gsavit 👋

Thank you for your contribution to fastlane and congrats on getting this pull request merged 🎉
The code change now lives in the master branch, however it wasn't released to RubyGems yet.
We usually ship about once a week, and your PR will be included in the next one.

Please let us know if this change requires an immediate release by adding a comment here 👍
We'll notify you once we shipped a new release with your changes 🚀

[fastlane-bot]

Congratulations! 🎉 This was released as part of fastlane 2.190.0 🚀