Add build detail notification to switch back to the normal dashboard

[agjohnson]

This adds a notification to just the detail view that links directly back to the same page on the normal dashboard.

• Requires https://github.com/readthedocs/readthedocs.org/pull/11208
• Fixes #284
• Refs https://github.com/readthedocs/readthedocs.org/issues/11209