fixup! maintenance: add new vfs-cache-move maintenance task

Author: mjcheetham

builtin/gc.c

@@ -1440,6 +1440,10 @@ static void migrate_pack(const char *srcdir, const char *dstdir,
 		if (files[i].move)
 			continue;
 
+		/* Files that never existed in originally have no clean up.*/
+		if (!file_exists(src.buf))
+			continue;
+
 		strbuf_setlen(&src, srclen);
 		strbuf_addstr(&src, files[i].ext);
 		if (unlink(src.buf))