Update build-validation workflow to remove signing step from local Maven publish

Author: YunchuWang

.github/workflows/build-validation.yml

@@ -141,7 +141,7 @@ jobs:
         uses: gradle/gradle-build-action@v2
 
       - name: Publish to local
-        run: ./gradlew publishToMavenLocal -x sign
+        run: ./gradlew publishToMavenLocal
 
       - name: Build azure functions sample
         run: ./gradlew azureFunctionsPackage