MDEV-17881: Fix a debug assertion

In 10.3, rec_is_metadata() takes a pointer, while in 10.4 it
takes a reference as a parameter. I ported this patch from
10.4 to 10.3, and then only ran a release build, not debug build.

storage/innobase/rem/rem0cmp.cc

@@ -797,7 +797,7 @@ cmp_dtuple_rec_with_match_bytes(
 			  & rec_get_info_bits(rec, rec_offs_comp(offsets)))) {
 		ut_ad(page_rec_is_first(rec, page_align(rec)));
 		ut_ad(!page_has_prev(page_align(rec)));
-		ut_ad(rec_is_metadata(rec, *index));
+		ut_ad(rec_is_metadata(rec, index));
 		return 1;
 	}