build(deps): bump pymongo in /fai-rag-app/fai-backend (#64)

Bumps [pymongo](https://github.com/mongodb/mongo-python-driver) from 4.6.1 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@4.6.1...4.6.3)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>