Fix: Lexing regex literal tokenisation

[PEZ]

What has Changed?

This fixes issue #463 by including an optional # in front of a string literal which gets regex literals tokenised as strings.

I think that regex literals should probably be tokenised to regex literals instead, but that is a bigger change, and this tiny change seems to fix the actual issue for the user. I propose we put the proper fix on the todo-list.

Please look at the tiny code change and help think about potential side effects, and help test that the change doesn't break things.

My Calva PR Checklist

I have:

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  • Figured if the change might have some side effects and tested those as well.
  • Smoke tested the extension as such.
• If need be, had a chat within the team about particular changes.

Ping @PEZ, @kstehn, @cfehse

[cfehse]

@PEZ

I don't see problems with the changed regex.