Document TableAlreadyExistsError in rename_table (#3289)

# Rationale for this change

Add a missing exception to `catalog.rename_table` method. 

## Are these changes tested?

No

## Are there any user-facing changes?

No

<!-- In the case of user-facing changes, please add the changelog label.
-->

Author: ebyhr

pyiceberg/catalog/__init__.py

@@ -545,6 +545,7 @@ def rename_table(self, from_identifier: str | Identifier, to_identifier: str | I
 
         Raises:
             NoSuchTableError: If a table with the name does not exist.
+            TableAlreadyExistsError: If the target table already exists.
         """
 
     @abstractmethod