Delete timeline event

Proposal

Delete an existing timeline event from manually in the UI.

Design

• Delete will be added to the "more actions" menu

• Clicking delete will prompt an "are you sure" modal, asking people to confirm they want to delete the timeline item.

  Modal header: Delete timeline event

  Modal body: Are you sure you want to delete this timeline event? This action can't be undone.

  Buttons: Delete (danger variant); Cancel

Figma file

Frontend

• Show form for deleting an event
• Call API when submitted

Backend

• Provide API to delete a timeline event

See Figma for latest designs: https://www.figma.com/file/01efUzilO8y3FZndx4Kt14/Incident-timelines-gitlab-com-and-330901?node-id=63%3A342