New core action names & other improvements

* [fastlane] Rename core actions and make aliases for backwards compatibility (#10939) via Mark Pirri
* [fastlane] Allow shell conversion when type is :shell_string (#10946) via Jimmy Dee
* [fastlane] Extend tab auto complete to work with bundler and custom commands (#11004) via Iulian Onofrei
* [spaceship] Handle updated T&Cs instructions (#11058) via Michał Ordon
* [docs template] Linkable headline instead of bolded text for actions (#11053) via Jan Piotrowski
* [frameit docs] Formatting/link fixes (#11060) via Jan Piotrowski
* [tests] Fix FastlaneCore::Helper.xcode_path for non-Mac environments (#11043) via Jan Piotrowski
* [tests] Only check for valid Xcode path when running on a Mac (#11045) via Jan Piotrowski

https://github.com/fastlane/fastlane/releases/tag/2.68.0
