Remove FF ci_order_subsequent_jobs_by_stage

It's already enabled by default.

Changelog: other

app/services/ci/after_requeue_job_service.rb

@@ -22,13 +22,9 @@ module Ci
     end
 
     def dependent_jobs
-      if ::Feature.enabled?(:ci_order_subsequent_jobs_by_stage, @processable.pipeline.project, default_enabled: :yaml)
-        stage_dependent_jobs
-          .or(needs_dependent_jobs.except(:preload))
-          .ordered_by_stage
-      else
-        stage_dependent_jobs | needs_dependent_jobs
-      end
+      stage_dependent_jobs
+        .or(needs_dependent_jobs.except(:preload))
+        .ordered_by_stage
     end
 
     def process(job)

config/feature_flags/development/ci_order_subsequent_jobs_by_stage.yml

----
-name: ci_order_subsequent_jobs_by_stage
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/77528
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/349977
-milestone: '14.7'
-type: development
-group: group::pipeline authoring
-default_enabled: true

spec/services/ci/pipeline_processing/atomic_processing_service_spec.rb

@@ -1043,22 +1043,6 @@ RSpec.describe Ci::PipelineProcessing::AtomicProcessingService do
         expect(all_builds_names).to eq(%w[A1 A2 B])
         expect(all_builds_statuses).to eq(%w[pending created created])
       end
-
-      context 'when the FF ci_order_subsequent_jobs_by_stage is disabled' do
-        before do
-          stub_feature_flags(ci_order_subsequent_jobs_by_stage: false)
-        end
-
-        it 'processes subsequent jobs in an incorrect order when playing first job' do
-          expect(all_builds_names).to eq(%w[A1 A2 B])
-          expect(all_builds_statuses).to eq(%w[manual skipped skipped])
-
-          play_manual_action('A1')
-
-          expect(all_builds_names).to eq(%w[A1 A2 B])
-          expect(all_builds_statuses).to eq(%w[pending created skipped])
-        end
-      end
     end
 
     private