Escape cpflow bootstrap metadata patch

Author: justin808

.github/workflows/cpflow-deploy-review-app.yml

@@ -75,7 +75,7 @@ jobs:
           gem install cpflow -v "5.0.0.rc.0" --no-document
           ruby -S cpflow generate-github-actions --staging-branch master
           # shellcheck disable=SC2016
-          ruby -0pi -e 'gsub!("so callers can pass `${{ vars.CPLN_CLI_VERSION }}` unconditionally.", "so callers can pass the repository variable value unconditionally."); gsub!("so callers can pass `${{ vars.CPFLOW_VERSION }}` unconditionally.", "so callers can pass the repository variable value unconditionally.")' .github/actions/cpflow-setup-environment/action.yml
+          ruby -0pi -e '$_.gsub!(/so callers can pass `\$\{\{ vars\.CPLN_CLI_VERSION \}\}` unconditionally\./, "so callers can pass the repository variable value unconditionally."); $_.gsub!(/so callers can pass `\$\{\{ vars\.CPFLOW_VERSION \}\}` unconditionally\./, "so callers can pass the repository variable value unconditionally.")' .github/actions/cpflow-setup-environment/action.yml
 
       - name: Validate required secrets and variables
         id: config