Fix doc link (googleapis#9200)

Author: WalterHub

bigquery/google/cloud/bigquery/job.py

@@ -2678,7 +2678,7 @@ def ddl_target_routine(self):
             for CREATE/DROP FUNCTION/PROCEDURE  queries.
 
         See:
-        https://cloud.google.com/bigquery/docs/reference/rest/v2/JobStatistics
+        https://cloud.google.com/bigquery/docs/reference/rest/v2/Job#jobstatistics
         """
         prop = self._job_statistics().get("ddlTargetRoutine")
         if prop is not None: