feat(visibility): Register flag for more aggressive sampling of `OrganizationTagsEndpoint` (#80330)

Related to https://github.com/getsentry/sentry/issues/61999, I'm going
to try a different sampling approach there, behind a feature flag.

src/sentry/features/temporary.py

@@ -473,6 +473,8 @@ def register_temporary_features(manager: FeatureManager):
     manager.add("organizations:starfish-wsv-chart-dropdown", OrganizationFeature, FeatureHandlerStrategy.FLAGPOLE, api_expose=False)
     # Allow organizations to configure all symbol sources.
     manager.add("organizations:symbol-sources", OrganizationFeature, FeatureHandlerStrategy.INTERNAL, default=True, api_expose=True)
+    # Enable static ClickHouse sampling for `OrganizationTagsEndpoint`
+    manager.add("organizations:tag-key-sample-n", OrganizationFeature, FeatureHandlerStrategy.FLAGPOLE, api_expose=False)
     # Enable team workflow notifications
     manager.add("organizations:team-workflow-notifications", OrganizationFeature, FeatureHandlerStrategy.FLAGPOLE, api_expose=False)
     # Enable feature to load more than 100 rows in performance trace view.