Bump hb requirement to 2.2.0
We are using hb_ot_var apis in various places. These have been introduced in harfbuzz 2.2.0.
2.2.0 is from 2018, so this should be safe.
We are using hb_ot_var apis in various places. These have been introduced in harfbuzz 2.2.0.
2.2.0 is from 2018, so this should be safe.