Revert unintended indentation

Author: michaelbautin

hnswlib/hnswalg.h

@@ -1513,7 +1513,7 @@ class HierarchicalNSW : public AlgorithmInterface<dist_t> {
         if (isMarkedDeleted(internalId)) {
             unsigned char *ll_cur = ((unsigned char *)get_linklist0(internalId)) + 2;
             *ll_cur &= ~DELETE_MARK;
-                num_deleted_ -= 1;
+            num_deleted_ -= 1;
             if (allow_replace_deleted_) {
                 std::unique_lock <std::mutex> lock_deleted_elements(deleted_elements_lock);
                 deleted_elements.erase(internalId);