fix duplicated error message

Signed-off-by: Bugen Zhao <i@bugenzhao.com>

e2e_test/ddl/invalid_operation.slt

@@ -253,7 +253,6 @@ SELECT * from msrc limit 0;
 # FIXME: improve the error message
 query error not found
 SELECT * from sink limit 0;
-----
 
 query I
 SELECT * from v limit 0;