Add minute limit banner

What does this MR do and why?

Describe in detail what your merge request does and why.

gitlab-com/Product#4035 (closed)

Create a banner informing users that free project CI/CD minutes will be limited to 400 minutes per month, effective June 1st 2022.

The banner is shown on these pages:

• Free projects:
  • Landing page
  • Settings
  • Settings > CI/CD
  • CI/CD > Pipelines
  • CI/CD > Jobs
  • CI/CD > Schedules
• Free groups:
  • Landing page
  • Settings
  • Settings > CI/CD

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