chore(python): remove CONTRIBUTING.rst from templates

Source-Link: googleapis/synthtool@c96fb11
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-python:latest@sha256:710b70faff81151657d89db6e028c23a1051787598c8276bdd8eef25c92da8ab

Author: gcf-owl-bot[bot]

.github/.OwlBot.lock.yaml

@@ -13,5 +13,5 @@
 # limitations under the License.
 docker:
   image: gcr.io/cloud-devrel-public-resources/owlbot-python:latest
-  digest: sha256:023a21377a2a00008057f99f0118edadc30a19d1636a3fee47189ebec2f3921c
-# created: 2025-03-31T16:51:40.130756953Z
+  digest: sha256:710b70faff81151657d89db6e028c23a1051787598c8276bdd8eef25c92da8ab
+# created: 2025-04-10T17:48:54.829145676Z

CONTRIBUTING.rst

@@ -157,6 +157,31 @@ Running System Tests
 
 - System tests will be run against an actual project. You should use local credentials from gcloud when possible. See `Best practices for application authentication <https://cloud.google.com/docs/authentication/best-practices-applications#local_development_and_testing_with_the>`__. Some tests require a service account. For those tests see `Authenticating as a service account <https://cloud.google.com/docs/authentication/production>`__.
 
+- You'll need to create composite
+  `indexes <https://cloud.google.com/datastore/docs/tools/indexconfig>`__
+  with the ``gcloud`` command line
+  `tool <https://developers.google.com/cloud/sdk/gcloud/>`__::
+
+   # Install the app (App Engine Command Line Interface) component.
+   $ gcloud components install app-engine-python
+
+   # Authenticate the gcloud tool with your account.
+   $ GOOGLE_APPLICATION_CREDENTIALS="path/to/app_credentials.json"
+   $ gcloud auth activate-service-account    > --key-file=${GOOGLE_APPLICATION_CREDENTIALS}
+
+   # Create the indexes
+   $ gcloud datastore indexes create tests/system/index.yaml
+
+- You'll also need stored data in your dataset. To populate this data, run::
+
+   $ python tests/system/utils/populate_datastore.py
+
+- If you make a mistake during development (i.e. a failing test that
+  prevents clean-up) you can clear all system test data from your
+  datastore instance via::
+
+   $ python tests/system/utils/clear_datastore.py
+
 - You'll need to create composite
   `indexes <https://cloud.google.com/datastore/docs/tools/indexconfig>`__
   with the ``gcloud`` command line