test: adds storage to list of system tests to run (#16578)

1. Ensures that `google-cloud-storage` system tests run when a PR is
created OR a new commit is pushed to an existing PR that includes files
from the google-cloud-storage package.
2. Sorts the list lexigraphically.

NOTE for googlers: this is paired with a similar list on google3 and
should match.

Partially resolves #16487 🦕

Author: chalmerlowe

.kokoro/system.sh

@@ -96,15 +96,16 @@ packages_with_system_tests=(
   "google-cloud-datastore"
   "google-cloud-dns"
   "google-cloud-error-reporting"
-  "sqlalchemy-spanner"
   "google-cloud-firestore"
   "google-cloud-logging"
   "google-cloud-ndb"
   "google-cloud-pubsub"
   "google-cloud-spanner"
+  "google-cloud-storage"
   "google-cloud-testutils"
-  "sqlalchemy-bigquery"
   "pandas-gbq"
+  "sqlalchemy-bigquery"
+  "sqlalchemy-spanner"
 )
 
 # A file for running system tests

packages/google-cloud-storage/noxfile.py

@@ -334,7 +334,7 @@ def system(session, test_type):
         session.skip(
             "Credentials must be set via environment variable GOOGLE_APPLICATION_CREDENTIALS"
         )
-    # mTLS tests requires pyopenssl.
+    # Install pyopenssl for mTLS testing.
     if os.environ.get("GOOGLE_API_USE_CLIENT_CERTIFICATE", "") == "true":
         session.install("pyopenssl")
     # Check if endpoint is being overriden for rerun_count