feat(mongodb): remove id from snapshot doc

Author: jremy42

docs/resources/mongodb_snapshot.md

@@ -39,8 +39,6 @@ The following arguments are supported:
 
 In addition to all arguments above, the following attributes are exported:
 
-- `id` - The unique identifier of the MongoDB® snapshot.
-
 - `instance_name` - The name of the MongoDB® instance from which the snapshot was created.
 
 - `size` - The size of the MongoDB® snapshot in bytes.