Bump ciso8601 from 2.3.0 to 2.3.1

Bumps [ciso8601](https://github.com/closeio/ciso8601) from 2.3.0 to 2.3.1.
- [Release notes](https://github.com/closeio/ciso8601/releases)
- [Changelog](https://github.com/closeio/ciso8601/blob/master/CHANGELOG.md)
- [Commits](closeio/ciso8601@v2.3.0...v2.3.1)

---
updated-dependencies:
- dependency-name: ciso8601
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

setup.py

@@ -116,7 +116,7 @@ def readme():
         "lz4==4.3.2",
         "typing_extensions==4.8.0",
         "charset-normalizer>=2.0.7",
-        "ciso8601==2.3.0",
+        "ciso8601==2.3.1",
         "iso8601==1.1.0",
         "pgpy==0.6.0",
         "python-magic==0.4.27",