fix: Add context manager return types (#356)

* docs: Add documentation for enums

fix: Add context manager return types

chore: Update gapic-generator-python to v1.8.1
PiperOrigin-RevId: 503210727

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packages/google-cloud-containeranalysis/google/cloud/devtools/containeranalysis_v1/services/container_analysis/client.py

@@ -1036,7 +1036,7 @@ def sample_get_vulnerability_occurrences_summary():
         # Done; return the response.
         return response
 
-    def __enter__(self):
+    def __enter__(self) -> "ContainerAnalysisClient":
         return self
 
     def __exit__(self, type, value, traceback):

packages/google-cloud-containeranalysis/samples/generated_samples/snippet_metadata_google.devtools.containeranalysis.v1.json

@@ -8,7 +8,7 @@
     ],
     "language": "PYTHON",
     "name": "google-cloud-containeranalysis",
-    "version": "2.11.0"
+    "version": "0.1.0"
   },
   "snippets": [
     {