Bumps MongoDb.Driver from 2.24.0 to 2.28.0

[Droxx]

Bumps MongoDb.Driver to address #7306

MongoDb.Driver introduces Strong-Named Assemblies in 2.28.0. Causing issues in environments with HotChocolate that are now using this version.

Closes #7306

[CLAassistant]

All committers have signed the CLA.

[michaelstaib]

MongoDB should have done a major version for this as it forces now updates to all libraries that we are using in unit tests that use mongo.

[michaelstaib]

@Droxx thank you for your work ... also the downstream work :)

[michaelstaib]

This will be part of 14 rc.1