Rust: fix old.dbscheme in downgrade script

Author: redsun82

rust/downgrades/b41e55c0dba14a139d01dbee713aca5efe5b818a/old.dbscheme

@@ -2049,19 +2049,19 @@ macro_block_exprs(
   unique int id: @macro_block_expr
 );
 
-#keyset[id]
-macro_block_expr_tail_exprs(
-  int id: @macro_block_expr ref,
-  int tail_expr: @expr ref
-);
-
 #keyset[id, index]
 macro_block_expr_statements(
   int id: @macro_block_expr ref,
   int index: int ref,
   int statement: @stmt ref
 );
 
+#keyset[id]
+macro_block_expr_tail_exprs(
+  int id: @macro_block_expr ref,
+  int tail_expr: @expr ref
+);
+
 macro_exprs(
   unique int id: @macro_expr
 );