Replace the last of the fastlane lanes with swift tooling

- move more sharable code to CI static methods
- merge `release_to_github` and `prepare_next_release` into one single command as they had dependencies on each other
- remove all traces of ruby and fastlane

ci_scripts/ci_common.sh

@@ -1,33 +1,9 @@
 #!/bin/sh
 
-setup_xcode_cloud_environment () {
-    # Return on failures
-    # Fail when expanding unset variables
-    # Trace each command before executing it
-    set -eEu
-
-    # Move to the project root
-    cd ..
-
-    # Prevent installing dependencies in system directories
-    echo 'export GEM_HOME=$HOME/.gem' >>~/.zshrc
-    echo 'export PATH=$GEM_HOME/bin:$PATH' >>~/.zshrc
-    echo 'export PATH="/usr/local/opt/ruby/bin:$PATH"' >> ~/.zshrc
-    echo 'export PATH="/Users/local/Library/Python/3.9/bin:$PATH"' >> ~/.zshrc
-
-    export GEM_HOME=$HOME/.gem
-    export PATH=$GEM_HOME/bin:$PATH
-    export PATH="/usr/local/opt/ruby/bin:$PATH"
-    export PATH="/Users/local/Library/Python/3.9/bin:$PATH"
-
-    # Things don't work well on the default ruby version
-    brew install ruby
-
-    gem install bundler
-
-    bundle config path vendor/bundle
-    bundle install --jobs 4 --retry 3
-}
+# Return on failures
+# Fail when expanding unset variables
+# Trace each command before executing it
+set -eEu
 
 install_xcode_cloud_brew_dependencies () {
     brew update && brew install xcodegen pkl getsentry/tools/sentry-cli