Fix another issue in loast fast borrow

Summary: Fixing another issue in the borrowed load analysis: python/cpython#138678

Reviewed By: mpage

Differential Revision: D81950973

fbshipit-source-id: f6663befbcc36b159cbb03a20354d4452e1e47f8

Author: DinoV

Python/flowgraph.c

@@ -2879,7 +2879,7 @@ optimize_load_fast(cfg_builder *g)
                     int num_pushed = _PyOpcode_num_pushed(opcode, oparg);
                     int net_pushed = num_pushed - num_popped;
                     assert(net_pushed >= 0);
-                    for (int i = 0; i < net_pushed; i++) {
+                    for (int j = 0; j < net_pushed; j++) {
                         PUSH_REF(i, NOT_LOCAL);
                     }
                     break;