Background
We would like all edits made through Suggested Edits to have meaningful edit summaries. Currently, "undo" edits are only saved with hashtag edit summaries if users do not add an edit summary, and these could be unclear to newcomers or other patrollers alike. We received a bug report hashtag edit summaries were causing standard edit summaries not to appear: T359006. We fixed this for rollback, this is the task to ensure it's also addressed for Undo.

Current behavior:

• Undo: when a user reverts (undo), we allow users to enter their edit summary with (optional) noted. If they leave this blank, the edit is only shown with the hashtag #suggestededit-patrol-undo1.0.

Requirements:

• If a user skips adding an edit summary to their undo action, add an automatic edit summary for them similar to how is done elsewhere in the app, "Undid revision XXXXX by User (talk) #suggestededit-patrol"
• Append a user-generated edit summary with #suggestededit-patrol