Fix `<!DOCTYPE html>` syntax highlighting (#9108)

Release Notes:

- Added `<!DOCTYPE html>` syntax highlighting ([4318](https://github.com/zed-industries/zed/issues/4318))
e1f8a1e8b2Max committed on 3/11/2024, 7:56:35 AM· committed by GitHubparent41dc5fc
1 file changedLine totals unavailable