Rollup of 5 pull requests
Successful merges:
- #78164 (Prefer regions with an `external_name` in `approx_universal_upper_bound`)
- #80003 (Fix overflow when converting ZST Vec to VecDeque)
- #80023 (Enhance error message when misspelled label to value in break expression)
- #80046 (Add more documentation to `Diagnostic` and `DiagnosticBuilder`)
- #80109 (Remove redundant and unreliable coverage test results)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
f3800db221