More interop test clean up

tonic-interop/test.sh

@@ -43,6 +43,6 @@ trap 'echo ":; killing test server"; kill ${SERVER_PID};' EXIT
 
 cargo run -p tonic-interop --bin client -- \
 --test_case=empty_unary,large_unary,client_streaming,server_streaming,ping_pong,\
-empty_stream,status_code_and_message
-# special_status_message,unimplemented_method,\
-# unimplemented_service,custom_metadata $ARG
+empty_stream,status_code_and_message,special_status_message $ARG
+# unimplemented_method,unimplemented_service,custom_metadata
+