Auto merge of #12637 - asajeffrey:constellation-use-reentrant-logging-mutex, r=emilio

Replaced mutex in constellation logging by a reentrant mutex.

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The double-panic in #12553 may be caused by using a non-reentrant lock, which panics on reetry. This PR adds a reentrant lock type (slightly annoyingly, the implementation in std isn't exported) and uses it for logging. cc @jdm

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12619.
- [X] These changes do not require tests because they are designed to remove a class of intermittents.

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