<!-- The PR description should answer 2 (maybe 3) important questions:
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### What
To stop us being confused between `Error` type and `Error` trait.
<!-- What is this PR trying to accomplish (and why, if it's not
obvious)? -->
<!-- Consider: do we need to add a changelog entry? -->
### How
Import `thiserror::Error` explicitly in place.
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steps)? -->
V3_GIT_ORIGIN_REV_ID: b930480927b2c64537960cfb69f2b2b30921f4fd