[CI] Validate Gradle and checkout branch to use as app name

Author: Stypox

.github/workflows/ci.yml

@@ -36,6 +36,16 @@ jobs:
       - name: Check out repository
         uses: actions/checkout@v4
 
+      - name: Make sure Gradle wrapper is legitimate
+        uses: gradle/actions/wrapper-validation@v5
+
+      - name: Create and checkout branch that will be used as app name
+        # push events already checked out the branch
+        if: github.event_name == 'pull_request'
+        env:
+          BRANCH: ${{ github.head_ref }}
+        run: git checkout -B "$BRANCH"
+
       - name: Set up Java JDK
         uses: actions/setup-java@v4
         with: