Chore(deps): Update pymongo requirement from <4.14 to <4.16

Updates the requirements on [pymongo](https://github.com/mongodb/mongo-python-driver) to permit the latest version.
- [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@0.4pre...4.15.0)

---
updated-dependencies:
- dependency-name: pymongo
  dependency-version: 4.15.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

pyproject.toml

@@ -134,7 +134,7 @@ optional-dependencies.doc = [
   "sphinxext-opengraph<1",
 ]
 optional-dependencies.mongodb = [
-  "pymongo<4.14",
+  "pymongo<4.16",
 ]
 optional-dependencies.release = [
   "build<2",