Add no-unescaped-entities to recommended configuration

[lencioni]

This rule was added by #681 and I think it should be added to the recommended configuration for the next major version bump.

[rauchg]

@ljharb I'm curious what the downsides are to not escaping '? Makes writing stuff pretty difficult, but I'm sure there's a good reason

[ljharb]

@rauchg The rule documentation should explain it; basically, it's highly likely there's a bug.

Separately, it shouldn't impact "writing stuff" at all, since straight quotes are typographically incorrect, and you don't need to escape curly quotes.