Removing Ruby 3.1

[Takahiro Kambe <taca%NetBSD.org@localhost>]

Hi.

Ruby 3.1 reached end of life on 26th March 2025 and I'll remove it
next week.

And these packages are targets to remove, too.

	databases/ruby-dbd-sqlite
	databases/ruby-ldap
	databases/ruby-sqlite
	devel/ruby-redmine50
	mail/ruby-mail27		(for redmine50)
	mail/ruby-roadie30-rails	(for redmine50)
	net/ruby-net-pop		(for redmine51/61 with ruby31)
	textproc/ruby-redcarpet35	(for redmine50)

-- 
Takahiro Kambe <taca%NetBSD.org@localhost>