Adding worker indexing flag

Author: Gavin Aguiar

tests/utils/testutils_docker.py

@@ -121,6 +121,7 @@ def create_container(self, image_repo: str, image_url: str,
         run_cmd.extend(["--cap-add", "SYS_ADMIN"])
         run_cmd.extend(["--device", "/dev/fuse"])
         run_cmd.extend(["-e", f"CONTAINER_NAME={_uuid}"])
+        run_cmd.extend(["-e", f"AzureWebJobsFeatureFlags=EnableWorkerIndexing"])
         run_cmd.extend(["-e",
                         "AzureWebJobsStorage="
                         f"{os.getenv('AzureWebJobsStorage')}"])