chore: remove codelabs/ samples (#9497)

These samples are no longer being maintained and do not contain any region tags (not referenced in docs).

Author: kweinmeister

.github/CODEOWNERS

@@ -31,7 +31,6 @@
 /cloudbuild/**/*                       @GoogleCloudPlatform/torus-dpe @GoogleCloudPlatform/python-samples-reviewers
 /cloud-sql/**/*                        @GoogleCloudPlatform/infra-db-dpes @GoogleCloudPlatform/python-samples-reviewers
 /cloud_tasks/**/*                      @GoogleCloudPlatform/infra-db-dpes @GoogleCloudPlatform/python-samples-reviewers
-/codelabs/**/*                         @GoogleCloudPlatform/python-samples-reviewers
 /composer/**/*                         @leahecole @rachael-ds @GoogleCloudPlatform/cloud-dpes-composer @GoogleCloudPlatform/python-samples-reviewers
 /compute/**/*                          @m-strzelczyk @GoogleCloudPlatform/dee-infra @GoogleCloudPlatform/python-samples-reviewers
 /container/**/*                        @GoogleCloudPlatform/dee-platform-ops @GoogleCloudPlatform/python-samples-reviewers