Move to pcre2

[dvzrv]

Hi! :wave:

I package pcre2 for Arch Linux. We are currently working on moving from pcre (unmaintained) to pcre2.

Not having any details on this project's situation: Would it be possible for this project to either drop the dependency on pcre-light or start relying on e.g. https://github.com/sjshuck/hs-pcre2 instead?