Update open-api/rest-catalog-open-api.yaml

Co-authored-by: Eduard Tudenhoefner <[email protected]>

Author: snazy

open-api/rest-catalog-open-api.yaml

@@ -145,9 +145,6 @@ paths:
         See [Security improvements in the Iceberg REST specification](https://github.com/apache/iceberg/issues/10537)
 
 
-        Old description follows
-
-
         Exchange credentials for a token using the OAuth2 client credentials flow or token exchange.