Bump multidict from 5.1.0 to 5.2.0

Bumps [multidict](https://github.com/aio-libs/multidict) from 5.1.0 to 5.2.0.
- [Release notes](https://github.com/aio-libs/multidict/releases)
- [Changelog](https://github.com/aio-libs/multidict/blob/master/CHANGES.rst)
- [Commits](aio-libs/multidict@v5.1.0...v5.2.0)

---
updated-dependencies:
- dependency-name: multidict
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements.txt

@@ -26,7 +26,7 @@ fonttools==4.27.1
     # via fdiff (setup.py)
 idna==3.2
     # via yarl
-multidict==5.1.0
+multidict==5.2.0
     # via
     #   aiohttp
     #   yarl