Bump git/ext/gitdb from 8ec2390 to 6a22706

Bumps [git/ext/gitdb](https://github.com/gitpython-developers/gitdb) from `8ec2390` to `6a22706`.
- [Commits](gitpython-developers/gitdb@8ec2390...6a22706)

---
updated-dependencies:
- dependency-name: git/ext/gitdb
  dependency-type: direct:production
...

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Author: dependabot[bot]