Bump cachetools from 4.2.0 to 4.2.1 (#430)

Bumps [cachetools](https://github.com/tkem/cachetools) from 4.2.0 to 4.2.1.
- [Release notes](https://github.com/tkem/cachetools/releases)
- [Changelog](https://github.com/tkem/cachetools/blob/master/CHANGELOG.rst)
- [Commits](tkem/cachetools@v4.2.0...v4.2.1)

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

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>
Co-authored-by: Mariatta Wijaya <[email protected]>

Author: dependabot-preview[bot]

requirements.txt

@@ -1,7 +1,7 @@
 cherry_picker==1.3.2
 aiohttp==3.7.4
 gidgethub==5.0.0
-cachetools==4.2.0
+cachetools==4.2.1
 redis==3.5.3
 celery==5.0.5
 sentry-sdk==1.0.0