Log Message:
devel/ruby-regexp_parser: update to 2.6.0

2.6.0 (2022-09-26)

Fixed

* fixed #referenced_expression for \g<0> (was nil, is now the Root exp)

* fixed #reference, #referenced_expression for recursion level backrefs

	- e.g. (a)(b)\k<-1+1>
	- #referenced_expression was nil, now it is the correct Group exp

* detect and raise for two more syntax errors when parsing String input

	- quantification of option switches (e.g. (?i)+)
	- invalid references (e.g. /\k<1>/)
	- these are a SyntaxError in Ruby, so could only be passed as a
          String

Added

* Regexp::Expression::Base#human_name

	- returns a nice, human-readable description of the expression

* Regexp::Expression::Base#optional?

	- returns true if the expression is quantified accordingly
          (e.g. with *, {,n})

* added a deprecation warning when calling #to_re on set members