Backticks should be auto-closed

[harpocrates]

When I type a backtick, it would be nice for it to auto-close with another backtick.

I can't think of a situation in which I would want an unpaired backtick. Aside from that, it means that my code remains lexically valid as I type out the backtick-delimited identifier (as opposed to being invalid until I hit the closing backtick).

[tgodzik]

Thanks for reporting! It should be quite easy to do like in https://github.com/scala/vscode-scala-syntax/pull/274/files though oposite and with `

[harpocrates]

Yeah, I'm doing right now, will open PR shortly.