As part of CLOUDP-124662, listCollections will no longer be allowed on the admin database in the atlasProxy. I believe that we never dump anything in admin for M0/M2/M5 so we should be safe to just ignore the admin DB when we're connected to atlasProxy.

Acceptance criteria:

• Check that we never dump anything in the admin DB for M0/M2/M5
• Check if we ever run listCollections on admin for mognorestore
• Don't run listCollections on admin if we detect we are connected to atlasProxy

Copying Nat's thoughts here:

• We are starting to work on restricting list collections on admin, since we don’t want to break users that use older versions of mongo-tools we decided just always return an empty list.
• But I checked the mongo restore code and see https://github.com/mongodb/mongo-tools/blob/9b523103ee33812bf76bb0f8e4b3987e825725ba/mongorestore/metadata.go#L400
• Will we break mongo restore in that case?
• Its also answering the item from TOOLS-3229 Check if we ever run listCollections on admin for mognorestore