Auto merge of #15827 - moonlightdrive:use-iflet-not-match, r=mbrubeck

replace match with if let

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Use `if let` instead of a `match` with a single pattern.

I'm not clear if/how this needs to be tested (beyond what's been checked-off below), so please let me know if there's more to do. Thanks!

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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 #15810

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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