use level but not 0 in neighbor_range(i, level, &begin, &end) (line 198) (#5005)

Summary:
just like line 95-103 in same file (\faiss\impl\HNSW.cpp):
```
void HNSW::clear_neighbor_tables(int level) {
    for (size_t i = 0; i < levels.size(); i++) {
        size_t begin, end;
        neighbor_range(i, level, &begin, &end);  // ✅ right：use `level`
        // ...
    }
}
```

Pull Request resolved: https://github.com/facebookresearch/faiss/pull/5005

Reviewed By: alibeklfc

Differential Revision: D100557031

Pulled By: mnorris11

fbshipit-source-id: b248a93a0d1385ef72b22962027586308800ac75

faiss/impl/HNSW.cpp

@@ -188,7 +188,7 @@ void HNSW::fill_with_random_links(size_t n) {
         for (size_t ii = 0; ii < elts.size(); ii++) {
             int i = elts[ii];
             size_t begin, end;
-            neighbor_range(i, 0, &begin, &end);
+            neighbor_range(i, level, &begin, &end);
             for (size_t j = begin; j < end; j++) {
                 int other = 0;
                 do {