Fix supported platform of pilot, and testflight action

[taisukeh]

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

The pilot action doesn't support android platform. I think it would be misleading.

Description

This change alos affects the testflight action.
https://github.com/fastlane/fastlane/blob/master/fastlane/lib/fastlane/actions/testflight.rb#L39

[KrauseFx]

Yeah, nice catch, thanks for the PR 👍 I think it also doesn't support macOS, right? It's only iOS

[taisukeh]

Right, fixed, thanks :)

[KrauseFx]

Awesome, thanks 👍

[fastlane-bot]

Hey @taisukeh 👋

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 2.56.0 🚀