unpack_trees(): start with a fresh lstat cache

We really want to avoid relying on stale information.

Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

unpack-trees.c

@@ -349,6 +349,9 @@ static int check_updates(struct unpack_trees_options *o)
 
 	progress = get_progress(o);
 
+	/* Start with clean cache to avoid using any possibly outdated info. */
+	invalidate_lstat_cache();
+
 	if (o->update)
 		git_attr_set_direction(GIT_ATTR_CHECKOUT, index);