Bump pymongo from 4.5.0 to 4.6.3 in /src

Bumps [pymongo](https://github.com/mongodb/mongo-python-driver) from 4.5.0 to 4.6.3.
- [Release notes](https://github.com/mongodb/mongo-python-driver/releases)
- [Changelog](https://github.com/mongodb/mongo-python-driver/blob/master/doc/changelog.rst)
- [Commits](mongodb/mongo-python-driver@4.5.0...4.6.3)

---
updated-dependencies:
- dependency-name: pymongo
  dependency-type: indirect
...

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