Bump yarl from 1.9.2 to 1.9.4

Bumps [yarl](https://github.com/aio-libs/yarl) from 1.9.2 to 1.9.4.
- [Release notes](https://github.com/aio-libs/yarl/releases)
- [Changelog](https://github.com/aio-libs/yarl/blob/master/CHANGES.rst)
- [Commits](aio-libs/yarl@v1.9.2...v1.9.4)

---
updated-dependencies:
- dependency-name: yarl
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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