Add MongoDB to datacontract cli

[philipp-lutz]

In a data mesh, mongoDB is a common operational datastore for lookup patterns and is notorious for schema drifts. It would benefit greatly from data contracts.

• Import: Create ODCS schema based on a collection's schema
• Export: Create mongoDB-flavored jsonschema (if necessary; maybe add --dialect option to datacontract export jsonschema
• Test: Connect to mongoDB collection and check if latest data adheres to data contract

[jschoedl]

Related to #993.

I agree that support for MongoDB would be nice in datacontract-cli. However, there are two things to be aware of:

• MongoDB it is not yet supported in ODCS (we would need to use serverType: custom and migrate to serverType: mongodb in case there is official support at one day).
• There is no native support for MongoDB in ibis, which we use for testing data contracts. This means that a custom adapter needs to be written. This is possible, but not trivial.

If you have capacity to work on this, feel free. Otherwise, it's unfortunately rather unlikely that this will be added soon.

When using Data Contract CLI as Python library, it may help that the import / export functionality can be extended natively. You might also consider proposing MongoDB as supported type in ODCS.