build(deps): bump pymongo from 3.13.0 to 4.6.3

Bumps [pymongo](https://github.com/mongodb/mongo-python-driver) from 3.13.0 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@3.13.0...4.6.3)

---
updated-dependencies:
- dependency-name: pymongo
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements.txt

@@ -2,5 +2,5 @@ Flask==0.12
 nltk==3.4.5
 MarkupSafe==1.1.1
 nose==1.3.0
-pymongo==3.13.0
+pymongo==4.6.3
 bashlex==0.12