Fix failed pipeline 530441 due to rubocop changes

What does this MR do and why?

Fix failed pipeline 530441 due to rubocop changes: https://jihulab.com/gitlab-cn/gitlab/-/jobs/4565454

• Fix rubocop
• Fix danger string interpolation (jh/danger/feature_flag/Dangerfile, @LXY1226 )
• Rename spec title ( under jh/spec/requests/api/integrations/, @songhuang )

---

cc EM @prajnamas