Remove FF ci_fix_order_of_subsequent_jobs

This FF was used to fix the order of subsequent jobs when running
a previous job.

Changelog: fixed

app/services/ci/after_requeue_job_service.rb

@@ -22,15 +22,9 @@ module Ci
     end
 
     def dependent_jobs
-      dependent_jobs = stage_dependent_jobs
-        .or(needs_dependent_jobs)
-        .ordered_by_stage
-
-      if ::Feature.enabled?(:ci_fix_order_of_subsequent_jobs, @processable.pipeline.project, default_enabled: :yaml)
-        dependent_jobs = ordered_by_dag(dependent_jobs)
-      end
-
-      dependent_jobs
+      ordered_by_dag(
+        stage_dependent_jobs.or(needs_dependent_jobs).ordered_by_stage
+      )
     end
 
     def process(job)

config/feature_flags/development/ci_fix_order_of_subsequent_jobs.yml

----
-name: ci_fix_order_of_subsequent_jobs
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/74394
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/345587
-milestone: '14.9'
-type: development
-group: group::pipeline authoring
-default_enabled: false

spec/services/ci/after_requeue_job_service_spec.rb

@@ -196,25 +196,6 @@ RSpec.describe Ci::AfterRequeueJobService, :sidekiq_inline do
         c2: 'created'
       )
     end
-
-    context 'when the FF ci_fix_order_of_subsequent_jobs is disabled' do
-      before do
-        stub_feature_flags(ci_fix_order_of_subsequent_jobs: false)
-      end
-
-      it 'does not mark b1 as processable', quarantine: 'https://gitlab.com/gitlab-org/gitlab/-/issues/356571' do
-        execute_after_requeue_service(a1)
-
-        check_jobs_statuses(
-          a1: 'pending',
-          a2: 'created',
-          b1: 'skipped',
-          b2: 'created',
-          c1: 'created',
-          c2: 'created'
-        )
-      end
-    end
   end
 
   private