Bump async-timeout from 3.0.1 to 4.0.0

Bumps [async-timeout](https://github.com/aio-libs/async_timeout) from 3.0.1 to 4.0.0.
- [Release notes](https://github.com/aio-libs/async_timeout/releases)
- [Changelog](https://github.com/aio-libs/async-timeout/blob/master/CHANGES.rst)
- [Commits](aio-libs/async-timeout@v3.0.1...v4.0.0)

---
updated-dependencies:
- dependency-name: async-timeout
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

requirements.txt

@@ -10,7 +10,7 @@ aiofiles==0.7.0
     # via fdiff (setup.py)
 aiohttp==3.7.4.post0
     # via fdiff (setup.py)
-async-timeout==3.0.1
+async-timeout==4.0.0
     # via aiohttp
 attrs==21.2.0
     # via aiohttp