Bump aiohttp from 3.7.4.post0 to 3.8.0 (#493)

Bumps [aiohttp](https://github.com/aio-libs/aiohttp) from 3.7.4.post0 to 3.8.0.
- [Release notes](https://github.com/aio-libs/aiohttp/releases)
- [Changelog](https://github.com/aio-libs/aiohttp/blob/master/CHANGES.rst)
- [Commits](aio-libs/aiohttp@v3.7.4.post0...v3.8.0)

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

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

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

Author: dependabot[bot]

requirements.txt

@@ -1,6 +1,6 @@
 # cherry_picker==2.0.0
 git+https://github.com/python/cherry-picker.git@main#egg=cherry_picker
-aiohttp==3.7.4.post0
+aiohttp==3.8.0
 gidgethub==5.0.1
 cachetools==4.2.4
 redis==3.5.3