(fix) moustache highlighting multiline

[dummdidumm]

Highlights moustache tags properly when the tag spans multiple lines
#478, #381

This fix looks suspicously simple, so it would be great if you could have a look at this @jasonlyu123 😄

[jasonlyu123]

Ummm... I didn't found any downside to this either. Seems like that part of the regex is not needed.

[dummdidumm]

Alright, then it really must be that simple 😄 Thanks for looking into it!

[jasonlyu123]

Feel dumb to have spent 40 minutes trying to make it match \\b([a-zA-Z\\-_:]+)=(\"|')(?=(.|\\s)*{ 🤣