Bump multidict from 5.2.0 to 6.0.2 (#670)

Bumps [multidict](https://github.com/aio-libs/multidict) from 5.2.0 to 6.0.2.
- [Release notes](https://github.com/aio-libs/multidict/releases)
- [Changelog](https://github.com/aio-libs/multidict/blob/master/CHANGES.rst)
- [Commits](aio-libs/multidict@v5.2.0...v6.0.2)

---
updated-dependencies:
- dependency-name: multidict
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Sam Bull <[email protected]>

Author: dependabot[bot]

requirements-dev.txt

@@ -11,7 +11,7 @@ flake8-bandit==2.1.2
 flake8-bugbear==22.1.11
 flake8-import-order==0.18.1
 flake8-requirements==1.5.2
-multidict==5.2.0
+multidict==6.0.2
 mypy==0.930
 pep257==0.7.0
 pre-commit==2.17.0