Cleanup update_deployment_after_transaction_commit feature flag

This commit cleans up the feature flag.

Changelog: performance

app/models/ci/build.rb

@@ -313,12 +313,6 @@ def with_preloads
       end
       after_transition pending: :running do |build|
-        unless build.update_deployment_after_transaction_commit?
-          Gitlab::Database.allow_cross_database_modification_within_transaction(url: 'https://gitlab.com/gitlab-org/gitlab/-/issues/338867') do
-            build.deployment&.run
-          end
-        end
-
         build.run_after_commit do
           build.pipeline.persistent_ref.create
@@ -339,35 +333,12 @@ def with_preloads
       end
       after_transition any => [:success] do |build|
-        unless build.update_deployment_after_transaction_commit?
-          Gitlab::Database.allow_cross_database_modification_within_transaction(url: 'https://gitlab.com/gitlab-org/gitlab/-/issues/338867') do
-            build.deployment&.succeed
-          end
-        end
-
         build.run_after_commit do
           BuildSuccessWorker.perform_async(id)
           PagesWorker.perform_async(:deploy, id) if build.pages_generator?
         end
       end
-      after_transition any => [:failed] do |build|
-        next unless build.project
-        next unless build.deployment
-
-        unless build.update_deployment_after_transaction_commit?
-          begin
-            Gitlab::Database.allow_cross_database_modification_within_transaction(url: 'https://gitlab.com/gitlab-org/gitlab/-/issues/338867') do
-              build.deployment.drop!
-            end
-          rescue StandardError => e
-            Gitlab::ErrorTracking.track_and_raise_for_dev_exception(e, build_id: build.id)
-          end
-        end
-
-        true
-      end
-
       after_transition any => [:failed] do |build|
         next unless build.project
@@ -380,25 +351,12 @@ def with_preloads
         end
       end
-      after_transition any => [:skipped, :canceled] do |build, transition|
-        unless build.update_deployment_after_transaction_commit?
-          Gitlab::Database.allow_cross_database_modification_within_transaction(url: 'https://gitlab.com/gitlab-org/gitlab/-/issues/338867') do
-            if transition.to_name == :skipped
-              build.deployment&.skip
-            else
-              build.deployment&.cancel
-            end
-          end
-        end
-      end
-
       # Synchronize Deployment Status
       # Please note that the data integirty is not assured because we can't use
       # a database transaction due to DB decomposition.
       after_transition do |build, transition|
         next if transition.loopback?
         next unless build.project
-        next unless build.update_deployment_after_transaction_commit?
         build.run_after_commit do
           build.deployment&.sync_status_with(build)
@@ -1120,12 +1078,6 @@ def shared_runner_build?
       runner&.instance_type?
     end
-    def update_deployment_after_transaction_commit?
-      strong_memoize(:update_deployment_after_transaction_commit) do
-        Feature.enabled?(:update_deployment_after_transaction_commit, project, default_enabled: :yaml)
-      end
-    end
-
     protected
     def run_status_commit_hooks!

config/feature_flags/development/update_deployment_after_transaction_commit.yml

----
-name: update_deployment_after_transaction_commit
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/71450
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/342021
-milestone: '14.4'
-type: development
-group: group::release
-default_enabled: false

spec/models/ci/build_spec.rb

@@ -1290,7 +1290,7 @@
     end
   end
-  shared_examples_for 'state transition as a deployable' do
+  describe 'state transition as a deployable' do
     subject { build.send(event) }
     let!(:build) { create(:ci_build, :with_deployment, :start_review_app, project: project, pipeline: pipeline) }
@@ -1332,6 +1332,22 @@
         expect(deployment).to be_running
       end
+
+      context 'when deployment is already running state' do
+        before do
+          build.deployment.success!
+        end
+
+        it 'does not change deployment status and tracks an error' do
+          expect(Gitlab::ErrorTracking)
+            .to receive(:track_exception).with(
+              instance_of(Deployment::StatusSyncError), deployment_id: deployment.id, build_id: build.id)
+
+          with_cross_database_modification_prevented do
+            expect { subject }.not_to change { deployment.reload.status }
+          end
+        end
+      end
     end
     context 'when transits to success' do
@@ -1399,36 +1415,6 @@
     end
   end
-  it_behaves_like 'state transition as a deployable' do
-    context 'when transits to running' do
-      let(:event) { :run! }
-
-      context 'when deployment is already running state' do
-        before do
-          build.deployment.success!
-        end
-
-        it 'does not change deployment status and tracks an error' do
-          expect(Gitlab::ErrorTracking)
-            .to receive(:track_exception).with(
-              instance_of(Deployment::StatusSyncError), deployment_id: deployment.id, build_id: build.id)
-
-          with_cross_database_modification_prevented do
-            expect { subject }.not_to change { deployment.reload.status }
-          end
-        end
-      end
-    end
-  end
-
-  context 'when update_deployment_after_transaction_commit feature flag is disabled' do
-    before do
-      stub_feature_flags(update_deployment_after_transaction_commit: false)
-    end
-
-    it_behaves_like 'state transition as a deployable'
-  end
-
   describe '#on_stop' do
     subject { build.on_stop }