This converts to TEST macro where it is trivial.
Some additional notable changes:
- simplify HAVE_LIBIDN #ifdef in test-dns-domain.c
- use saved_argc/saved_argv in test-copy.c, test-path-util.c,
test-tmpfiles.c and test-unit-file.c
This API is a complete mess. We forgot to do a hashed comparison for duplicate
entries and we use a direct pointer comparison. For trivial_hash_ops the result
is the same. For all other case, it's not. Fixing this properly will require
auditing all the uses of set_put() and ordered_set_put(). For now, let's just
acknowledge the breakage.