GitHub API Action, Setup Travis Action and More

* GitHub API action github_api (#8971) via Tom Meier
* Style actions on docs.fastlane.tools (#9894) via Orta
* Typo fixes (#9900) via Simon Brüchner
* Remove trailing command in gym docs (#9739) via Felix Krause
* Add link to available plugins in action docs (#9892) via Felix Krause
* Update maximum plugin score (#9883) via Felix Krause
* Disable blockchain rule in rubocop (#9891) via Felix Krause
* Add new setup_travis action (#9880) via Felix Krause
* Add ancestry_path parameter to changelog_from_git_commits (#9758) via DmitryArbuzov
* Fix upload of crashlytics symbols for tvOS apps (#9866) via Aman Gupta
* Allow using pathspec in git_commit action (#9867) via thii
* Disable flaky Jenkins tests (#9868) via Felix Krause

https://github.com/fastlane/fastlane/releases/tag/2.50.0
