move `auto_cancelable_pipelines` method to `create_pipeline_service.rb`

app/models/ci/pipeline.rb

@@ -127,14 +127,6 @@ module Ci
       where.not(duration: nil).sum(:duration)
     end
 
-    def auto_cancelable_pipelines
-      project.pipelines
-        .where(ref: ref)
-        .where.not(id: id)
-        .where.not(sha: project.repository.sha_from_ref(ref))
-        .created_or_pending
-    end
-
     def stage(name)
       stage = Ci::Stage.new(self, name: name)
       stage unless stage.statuses_count.zero?

app/services/ci/create_pipeline_service.rb

@@ -66,8 +66,7 @@ module Ci
     end
 
     def cancel_pending_pipelines
-      Gitlab::OptimisticLocking.retry_lock(
-        pipeline.auto_cancelable_pipelines) do |cancelables|
+      Gitlab::OptimisticLocking.retry_lock(auto_cancelable_pipelines) do |cancelables|
         cancelables.find_each do |cancelable|
           cancelable.cancel_running
           cancelable.update_attributes(auto_canceled_by: pipeline.id)
@@ -75,6 +74,14 @@ module Ci
       end
     end
 
+    def auto_cancelable_pipelines
+      project.pipelines
+        .where(ref: pipeline.ref)
+        .where.not(id: pipeline.id)
+        .where.not(sha: project.repository.sha_from_ref(pipeline.ref))
+        .created_or_pending
+    end
+
     def commit
       @commit ||= project.commit(origin_sha || origin_ref)
     end