Bump deps/coqutil from 886fb67 to de47a67

Bumps [deps/coqutil](https://github.com/mit-plv/coqutil) from `886fb67` to `de47a67`.
- [Release notes](https://github.com/mit-plv/coqutil/releases)
- [Commits](mit-plv/coqutil@886fb67...de47a67)

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

Signed-off-by: dependabot[bot] <support@github.com>