runtime(scala): Fix Scala highlighting string literal as type param (vim/vim#13070)
Since https://docs.scala-lang.org/sips/42.type.html which is implemented
in Scala 2.13 and in Scala 3 it possible to use string literals as
singleton types. So code like
```
someFunc["abc"]
```
is valid. Currently this code is not hightlighted correctly and worse if
there is an unclosed `(` in the string it breaks the formating in the
rest of the file.
I also submitted this patch to the mentioned project for this runtime
file: https://github.com/derekwyatt/vim-scala/pull/173 But there are no
commits there over the last 2 years and no response in the week since I
created it. Also the last change to the Scala syntax file:
https://github.com/vim/vim/pull/9594 is yet to be backported to that
repo. Therefore I am opening this PR as well to get some feedback on how
to proceed to get this fixed.
0661033075
Co-authored-by: Emil Ejbyfeldt <eejbyfeldt@liveintent.com>