4625: Partially fix displaying inlay hints in Github PR diff views r=matklad a=Veetaha
See the comment in https://github.com/rust-analyzer/rust-analyzer/issues/4608#issuecomment-63424257
It partially fixes the left side of diff view (the one where old code is displayed), but the diff editor with new code changes still has `file` scheme and will proceed displaying inlay hints...
4629: Fix the `should_panic` snippet r=matklad a=eminence
Closes#4628
Co-authored-by: veetaha <veetaha2@gmail.com>
Co-authored-by: Andrew Chin <achin@eminence32.net>