fix test commands to match POSIX
fix test commands to match POSIX

The == operator does not exist in POSIX (it's a feature some shells like
bash adds), so use = instead to work with all standard shells.

icing/mod_h2,r4-keisuke/mod_h2,icing/mod_h2,icing/mod_h2,r4-keisuke/mod_h2,r4-keisuke/mod_h2,r4-keisuke/mod_h2,r4-keisuke/mod_h2,icing/mod_h2,icing/mod_h2,r4-keisuke/mod_h2