Bump deps/coqutil from 0f3b370 to f12ff02

Bumps [deps/coqutil](https://github.com/mit-plv/coqutil) from `0f3b370` to `f12ff02`.
- [Release notes](https://github.com/mit-plv/coqutil/releases)
- [Commits](mit-plv/coqutil@0f3b370...f12ff02)

---
updated-dependencies:
- dependency-name: deps/coqutil
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]