Enable DAG support by default

This toggles the ci_dag_support flag to be on by default.
This relies on ci_dag_limit_needs to be present to reduce
amount of inter-dependencies between jobs

app/models/ci/build.rb

@@ -716,7 +716,7 @@ module Ci
       depended_jobs = depends_on_builds
 
       # find all jobs that are needed
-      if Feature.enabled?(:ci_dag_support, project) && needs.exists?
+      if Feature.enabled?(:ci_dag_support, project, default_enabled: true) && needs.exists?
         depended_jobs = depended_jobs.where(name: needs.select(:name))
       end
 

app/services/ci/process_pipeline_service.rb

@@ -40,7 +40,7 @@ module Ci
 
     def process_builds_with_needs(trigger_build_ids)
       return false unless trigger_build_ids.present?
-      return false unless Feature.enabled?(:ci_dag_support, project)
+      return false unless Feature.enabled?(:ci_dag_support, project, default_enabled: true)
 
       # rubocop: disable CodeReuse/ActiveRecord
       trigger_build_names = pipeline.statuses
@@ -97,7 +97,7 @@ module Ci
     # rubocop: enable CodeReuse/ActiveRecord
 
     def created_processables_without_needs
-      if Feature.enabled?(:ci_dag_support, project)
+      if Feature.enabled?(:ci_dag_support, project, default_enabled: true)
         pipeline.processables.created.without_needs
       else
         pipeline.processables.created