The TTF files are not served or used for anything else than converting
them to woff and woff2 formats, so there is no need to store them in the
git repo. In case a new format comes along, we would need to fetch these
from the git history or from upstream sources.
Change-Id: Iedc9162011b3b37587a2a176949afde6878d122d
Due to the nature of the script, Tiben usually has high ascent and descent
values. Use a variant of BabelStoneTibetan to have lesser ascent, descent
values for modern, frequently used Tibetan
Bug: T283122
Change-Id: I902af894b0e4d6f375981f13548be49405fb3602
