Mark gradlew as executable in the repo and delete Github action step that manually used to do that

Author: jamesdooleymsft

.github/workflows/gradle.yml

@@ -16,9 +16,6 @@ jobs:
       uses: actions/setup-java@v1
       with:
         java-version: 1.11
-
-    - name: Make gradle useable
-      run: chmod +x ./gradlew
-      
+   
     - name: Test with Gradle
       run: ./gradlew test