build(deps): bump slang from e13feb8 to f904c15

Bumps [slang](https://github.com/MikePopoloski/slang) from `e13feb8` to `f904c15`.
- [Release notes](https://github.com/MikePopoloski/slang/releases)
- [Commits](MikePopoloski/slang@e13feb8...f904c15)

---
updated-dependencies:
- dependency-name: slang
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>