Add GH workflow step with adding +x permission for gradlew

.github/workflows/gradle.yml

@@ -58,6 +58,9 @@ jobs:
         java-version: '21'
         distribution: 'temurin'
 
+    - name: Grant execute permission for gradlew
+      run: chmod +x gradlew
+
     # Generates and submits a dependency graph, enabling Dependabot Alerts for all project dependencies.
     # See: https://github.com/gradle/actions/blob/main/dependency-submission/README.md
     - name: Generate and submit dependency graph