chore: Update gapic-generator-python to v1.9.0 (#171)

* chore: Update gapic-generator-python to v1.9.0

PiperOrigin-RevId: 517425588

Source-Link: googleapis/googleapis@33c93eb

Source-Link: googleapis/googleapis-gen@d5f5978
Copy-Tag: eyJwIjoiLmdpdGh1Yi8uT3dsQm90LnlhbWwiLCJoIjoiZDVmNTk3ODlkMTlmYzQzMjcwZmYyMTI0OTY3ZDRlYzg5OTJiOGU4ZiJ9

* 🦉 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>

samples/generated_samples/snippet_metadata_google.cloud.datafusion.v1.json

@@ -8,7 +8,7 @@
     ],
     "language": "PYTHON",
     "name": "google-cloud-data-fusion",
-    "version": "1.8.0"
+    "version": "0.1.0"
   },
   "snippets": [
     {