chore: Python code samples migrated to python-doc-samples (#348)

* Python code samples migrated to python-doc-samples

For more details, please check GoogleCloudPlatform/python-docs-samples#8529 and http://b/257074849

* 🦉 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>

Author: msampathkumar

packages/google-cloud-containeranalysis/samples/README.md

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+Samples migrated
+================
+
+New location: https://github.com/GoogleCloudPlatform/python-docs-samples/tree/main/containeranalysis/snippets