Remove better-regex rule from recommended list

[fregante]

The rule uses a package "Published 7 years ago" https://www.npmjs.com/package/clean-regexp and it's the source of a lot of issues. Currently open:

• better-regex autofix breaks regular expression syntax: /|/g -> //g #2314
• better-regex rule breaks regex #1754
• better-regex proposes to replace [~^] with [^~] #1626
• unicorn/better-regex autofix breaks "match all" in multiline regexps  #895

Then check out regexp-tree issues

I disable it rather often, I suggest removing it from the recommended list or dropping/extracting the rule altogether.