Escape special characters in filter search
Escape special characters in filter search

At the moment if users enter a specila character inside
a filter search box, for example `*` in "organisations filter,
Javascript function will error

This amendment will escape these characters.

Borrowed from https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions#Escaping

alphagov/finder-frontend,alphagov/finder-frontend,alphagov/finder-frontend,alphagov/finder-frontend