feat(lint): remove unneeded parentheses around expressions

[mvorisek]

Modernize code using eslint advisory introduced in GH-2596. This PR focuses on fixing no-extra-parens rule with a help or a custom rule output filter.

[mvorisek]

TODO: unify hex escape case - see #2607 (comment)

@lubber-de fixing stylelint for upper case colors can be done easily with 'color-hex-case': 'upper' configuration, but I have checked the most commonly used coding standards and it seems lower case is used much more. Also advised by CS guides like: https://google.github.io/styleguide/htmlcssguide.html and https://docs.ckan.org/en/2.9/contributing/css.html

so I prefer to stay with the default LC for LESS/CSS colors and UC for escapes in JS.

Unified LC is not (easily) possible, as Unicorn has no configuration for it. Also UC for escapes in the only option with PHP CS Fixer, so it seems to be well accepted casing.

So if ok with you, I prefer too keep the casing rules as they are (and as default by the recommended CS AirBnb/Unicorn/Stylelint configs).

[lubber-de]

LGTM