Fix reference link typo

Author: warsaw

peps/pep-0694.rst

@@ -537,7 +537,7 @@ the final chunk, which **MUST** be either:
   file upload.
 * ``202 Accepted`` if the server accepts the last chunk, but must process it asynchronously.  In
   this case, the client should query the :ref:`session status <session-response>` periodically until
-  the uploaded :ref:`file status <session-file>` transitions to ``complete``.
+  the uploaded :ref:`file status <session-files>` transitions to ``complete``.
 
 The final chunk of data **MUST** include the ``Upload-Complete: ?1`` header, since at that point the
 entire file has been uploaded.