chore(python): allow client documentation to be customized in README (#413)

* chore(python): allow client documentation to be customized in README

Source-Link: googleapis/synthtool@95d9289
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-python:latest@sha256:c8878270182edaab99f2927969d4f700c3af265accd472c3425deedff2b7fd93

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: Anthonios Partheniou <[email protected]>

Author: gcf-owl-bot[bot]

packages/google-cloud-dlp/.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:e7bb19d47c13839fe8c147e50e02e8b6cf5da8edd1af8b82208cd6f66cc2829c
-# created: 2022-07-05T18:31:20.838186805Z 
+  digest: sha256:c8878270182edaab99f2927969d4f700c3af265accd472c3425deedff2b7fd93
+# created: 2022-07-14T01:58:16.015625351Z

packages/google-cloud-dlp/README.rst

@@ -55,18 +55,22 @@ Code samples and snippets live in the `samples/` folder.
 
 Supported Python Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^^
-Our client libraries are compatible with all current [active](https://devguide.python.org/devcycle/#in-development-main-branch) and [maintenance](https://devguide.python.org/devcycle/#maintenance-branches) versions of
+Our client libraries are compatible with all current `active`_ and `maintenance`_ versions of
 Python.
 
 Python >= 3.7
 
+.. _active: https://devguide.python.org/devcycle/#in-development-main-branch
+.. _maintenance: https://devguide.python.org/devcycle/#maintenance-branches
+
 Unsupported Python Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Python <= 3.6
 
-If you are using an [end-of-life](https://devguide.python.org/devcycle/#end-of-life-branches)
+If you are using an `end-of-life`_
 version of Python, we recommend that you update as soon as possible to an actively supported version.
 
+.. _end-of-life: https://devguide.python.org/devcycle/#end-of-life-branches
 
 Mac/Linux
 ^^^^^^^^^