Bump harfbuzz-sys from 0.3.3 to 0.3.4
Bump harfbuzz-sys from 0.3.3 to 0.3.4

Bumps [harfbuzz-sys](https://github.com/servo/rust-harfbuzz) from 0.3.3 to 0.3.4.
- [Release notes](https://github.com/servo/rust-harfbuzz/releases)
- [Commits](https://github.com/servo/rust-harfbuzz/commits/harfbuzz-sys-v0.3.4)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
KiChjang/servo,splav/servo,KiChjang/servo,splav/servo,splav/servo,splav/servo,KiChjang/servo,KiChjang/servo,splav/servo,splav/servo,KiChjang/servo,splav/servo,splav/servo,KiChjang/servo,KiChjang/servo,KiChjang/servo,splav/servo,KiChjang/servo,KiChjang/servo,splav/servo