added worker spec

spec/workers/propagate_project_service_worker_spec.rb

+require 'spec_helper'
+
+describe PruneOldEventsWorker do
+  describe '#perform' do
+    let!(:service_template) do
+      PushoverService.create(
+        template: true,
+        properties: {
+          device: 'MyDevice',
+          sound: 'mic',
+          priority: 4,
+          api_key: '123456789'
+        })
+    end
+
+    let!(:project) { create(:empty_project) }
+
+    it 'creates services for projects' do
+      expect { subject.perform }.to change { Service.count }.by(1)
+    end
+
+    it 'does not create the service if it exists already' do
+      Service.build_from_template(project.id, service_template).save!
+
+      expect { subject.perform }.not_to change { Service.count }
+    end
+
+    it 'creates the service containing the template attributes' do
+      subject.perform
+
+      service = Service.find_by(service_template.merge(project_id: project.id, template: false))
+
+      expect(service).not_to be_nil
+    end
+  end
+end