Update code coverage for CI build asynchronously

app/workers/build_coverage_worker.rb

+class BuildCoverageWorker
+  include Sidekiq::Worker
+  sidekiq_options queue: :default
+
+  def perform(build_id)
+    Ci::Build.find_by(id: build_id)
+      .try(:update_coverage)
+  end
+end

spec/workers/build_coverage_worker_spec.rb

+require 'spec_helper'
+
+describe BuildCoverageWorker do
+  describe '#perform' do
+    context 'when build exists' do
+      let!(:build) { create(:ci_build) }
+
+      it 'updates code coverage' do
+        expect_any_instance_of(Ci::Build)
+          .to receive(:update_coverage)
+
+        described_class.new.perform(build.id)
+      end
+    end
+
+    context 'when build does not exist' do
+      it 'does not raise exception' do
+        expect { described_class.new.perform(123) }
+          .not_to raise_error
+      end
+    end
+  end
+end