feat(python): add OciClient and OciClientV2 to additional_init_exports (#712)

Add OCI client exports so they survive Fern regeneration of __init__.py.
Follows the same pattern as BedrockClient/SagemakerClient.

Related: cohere-ai/cohere-python#718

Author: fede-kamel

fern/apis/sdks/generators.yml

@@ -171,6 +171,10 @@ groups:
             - from: aws_client
               imports:
                 - AwsClient
+            - from: oci_client
+              imports:
+                - OciClient
+                - OciClientV2
             - from: client_v2
               imports:
                 - AsyncClientV2