More stable spaceship, improved frameit, other improvements

* Make waiting for build processing more stable by retrying failed requests (#7762)
* Fix FastlaneRequire#gem_installed? to handle already-loaded libs (#7771)
* [supply] Added support for google service account credentials via environment variable (#7748)
* Update in-code documentation tool calls to use new fastlane syntax (#7751)
* Update screengrab tooling and dependency versions (#7766)
* Update gemspec to require correct version of Play API (#7763)
* Fix frameit 'easy mode' problem in landscape (#7759)
* frameit: support resuming of interrupted downloads of frames (#7750)
* Store spaceship and frameit config in ~/.fastlane (#7743)
* Detect if session was set via env variable if session is invalid, and show appropriate error message (#7742)

https://github.com/fastlane/fastlane/releases/tag/2.6.0
