Do not save associated records for pipeline builds twice

lib/gitlab/ci/pipeline/chain/populate.rb

@@ -14,14 +14,10 @@ module Gitlab
             @command.seeds_block&.call(pipeline)
             ##
-            # Populate pipeline with all stages and builds from pipeline seeds.
+            # Populate pipeline with all stages, and stages with builds.
             #
             pipeline.stage_seeds.each do |stage|
               pipeline.stages << stage.to_resource
-
-              stage.seeds.each do |build|
-                pipeline.builds << build.to_resource
-              end
             end
             if pipeline.stages.none?

spec/lib/gitlab/ci/pipeline/chain/populate_spec.rb

@@ -35,11 +35,6 @@ describe Gitlab::Ci::Pipeline::Chain::Populate do
     it 'populates pipeline with stages' do
       expect(pipeline.stages).to be_one
       expect(pipeline.stages.first).not_to be_persisted
-    end
-
-    it 'populates pipeline with builds' do
-      expect(pipeline.builds).to be_one
-      expect(pipeline.builds.first).not_to be_persisted
       expect(pipeline.stages.first.builds).to be_one
       expect(pipeline.stages.first.builds.first).not_to be_persisted
     end
@@ -151,8 +146,8 @@ describe Gitlab::Ci::Pipeline::Chain::Populate do
       step.perform!
       expect(pipeline.stages.size).to eq 1
-      expect(pipeline.builds.size).to eq 1
-      expect(pipeline.builds.first.name).to eq 'rspec'
+      expect(pipeline.stages.first.builds.size).to eq 1
+      expect(pipeline.stages.first.builds.first.name).to eq 'rspec'
     end
   end
 end