Setup ruby in workflow

.github/workflows/build-and-test-ios-app.yml

@@ -16,8 +16,13 @@ jobs:
     steps:
       - uses: actions/checkout@v2
 
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: '3.3.4' # Not needed with a `.ruby-version` or `.tool-versions`
+          bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+
       - name: Update Bundler
-        run: whoami && ruby --version && bundle update
+        run: bundle update
 
       - name: Check static code quality of iOS App
         run: bundle exec fastlane swift_lint