tools: relax lint rule for regexps

Relax the rule for maximum line length in JS files if the line contains
a regular expression literal. This will avoid the need to convert a
regular expression literal into a RegExp constructor call broken across
multiple lines in order to satisfy the maximum line length rule. That
practice hampers readability.

PR-URL: https://github.com/nodejs/node/pull/12807


Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Yuta Hiroto <hello@about-hiroppy.com>
Reviewed-By: Сковорода Никита Андреевич <chalkerx@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>