Merge branch '353217_remove_spread_parallel_import_ff' into 'master'

Remove feature flag `spread_parallel_import`

See merge request gitlab-org/gitlab!83608

config/feature_flags/development/spread_parallel_import.yml

----
-name: spread_parallel_import
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/81026
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/353217
-milestone: '14.9'
-type: development
-group: group::source code
-default_enabled: true

lib/gitlab/github_import/parallel_scheduling.rb

@@ -72,7 +72,7 @@ module Gitlab
       # Imports all objects in parallel by scheduling a Sidekiq job for every
       # individual object.
       def parallel_import
-        if Feature.enabled?(:spread_parallel_import, default_enabled: :yaml) && parallel_import_batch.present?
+        if parallel_import_batch.present?
           spread_parallel_import
         else
           parallel_import_deprecated

spec/lib/gitlab/github_import/parallel_scheduling_spec.rb

@@ -295,25 +295,6 @@ RSpec.describe Gitlab::GithubImport::ParallelScheduling do
         importer.parallel_import
       end
     end
-
-    context 'when FF is disabled' do
-      before do
-        stub_feature_flags(spread_parallel_import: false)
-      end
-
-      it 'imports data in parallel' do
-        expect(importer)
-          .to receive(:each_object_to_import)
-          .and_yield(object)
-
-        expect(worker_class)
-          .to receive(:perform_async)
-          .with(project.id, { title: 'Foo' }, an_instance_of(String))
-
-        expect(importer.parallel_import)
-          .to be_an_instance_of(Gitlab::JobWaiter)
-      end
-    end
   end
 
   describe '#each_object_to_import' do