Fixed XcodeCloud release workflows (#268)

* Export python 3.9 path and fix towncrier
* Fix Xcode Cloud git setup

ci_scripts/ci_common.sh

@@ -13,10 +13,12 @@ setup_environment () {
     echo 'export GEM_HOME=$HOME/.gem' >>~/.zshrc
     echo 'export PATH=$GEM_HOME/bin:$PATH' >>~/.zshrc
     echo 'export PATH="/usr/local/opt/ruby@2.7/bin:$PATH"' >> ~/.zshrc
+    echo 'export PATH="/Users/local/Library/Python/3.9/bin:$PATH"' >> ~/.zshrc
 
     export GEM_HOME=$HOME/.gem
     export PATH=$GEM_HOME/bin:$PATH
     export PATH="/usr/local/opt/ruby@2.7/bin:$PATH"
+    export PATH="/Users/local/Library/Python/3.9/bin:$PATH"
 
     # Things don't work well on the default ruby version
     brew install "ruby@2.7"

ci_scripts/ci_post_xcodebuild.sh

@@ -8,6 +8,7 @@ if [ "$CI_WORKFLOW" = "Release" ]; then
     install_python_dependencies
 
     bundle exec fastlane release_to_github
+    bundle exec fastlane prepare_next_release
 fi
 
 # Upload dsyms no matter the workflow