chore(flags): add feature flag to temporary.py (#77299)

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Author: michellewzhang

src/sentry/features/temporary.py

@@ -125,6 +125,8 @@ def register_temporary_features(manager: FeatureManager):
     manager.add("organizations:escalating-issues-v2", OrganizationFeature, FeatureHandlerStrategy.INTERNAL, api_expose=False)
     # Enable emiting escalating data to the metrics backend
     manager.add("organizations:escalating-metrics-backend", OrganizationFeature, FeatureHandlerStrategy.INTERNAL, api_expose=False)
+    # Enable feature flag UI in issue details
+    manager.add("organizations:feature-flag-ui", OrganizationFeature, FeatureHandlerStrategy.FLAGPOLE, api_expose=True)
     # Enable disabling gitlab integrations when broken is detected
     manager.add("organizations:gitlab-disable-on-broken", OrganizationFeature, FeatureHandlerStrategy.FLAGPOLE, api_expose=False)
     # Enable only calculating a secondary hash when needed