CNJR-0000: Use Gen1 Gcloud function env

Fixes "ERROR: (gcloud.functions.deploy) Invalid value for [--runtime]: python37 is not a supported runtime on GCF 2nd gen.
  Use `gcloud functions runtimes list` to get a list of available runtimes" error in GCP test

ci/test_suites/authenticators_gcp/deploy_function.sh

@@ -68,7 +68,7 @@ deploy_function() {
   cd "$GCF_SOURCE_DIR"
 
   echo "-- Deploying function: $GCF_FUNC_NAME"
-  gcloud functions deploy "$GCF_FUNC_NAME" --runtime python37 --trigger-http --quiet
+  gcloud functions deploy "$GCF_FUNC_NAME" --no-gen2 --runtime python37 --trigger-http --quiet
 
   echo '-> deploy_function done'
 }