Add regression tests for a few fixed issues with E-needs-test

[jakubadamw]

Closes #45689.
Closes #66805.
Closes #82646.
Closes #99478.
Closes #146398.

LLM disclosure: I used an LLM to identify best candidate issues (labelled as E-needs-test, unclaimed, with sensible reproducible examples etc)

All the tests have been verified to pass in the current nightly and reproduce in the nightlies in which they were reported to fail in/released around the date of the issues’ creation.

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[zakrad]

seems we both pushed for #159559, mind dropping it from batch since it was assigned

[jakubadamw]

seems we both pushed for #159559, mind dropping it from batch since it was assigned

@zakrad, oh, of course! 🙂

[jackh726]

@bors r+ rollup

[rust-bors]

📌 Commit d448db8 has been approved by jackh726

It is now in the queue for this repository.

🌲 The tree is currently closed for pull requests below priority 10. This pull request will be tested once the tree is reopened.

Reason for tree closure: Main branch is broken