sysutils/puppet6: Mark BROKEN with Ruby 3.x

<phase: stage >

> Staging for puppet6-6.26.0

> Generating temporary packing list

> Creating groups.

> Creating users

/usr/local/lib/ruby/3.0/fileutils.rb:206:in `mkdir_p': wrong number of arguments (given 2, expected 1) (ArgumentError)
from /wrkdirs/usr/ports/sysutils/puppet6/work/puppet-6.26.0/install.rb:80:in `block in do_libs'
from /wrkdirs/usr/ports/sysutils/puppet6/work/puppet-6.26.0/install.rb:76:in `each'
from /wrkdirs/usr/ports/sysutils/puppet6/work/puppet-6.26.0/install.rb:76:in `do_libs'
from /wrkdirs/usr/ports/sysutils/puppet6/work/puppet-6.26.0/install.rb:496:in `block in <main>'
from /usr/local/lib/ruby/3.0/fileutils.rb:139:in `chdir'
from /usr/local/lib/ruby/3.0/fileutils.rb:139:in `cd'
from /wrkdirs/usr/ports/sysutils/puppet6/work/puppet-6.26.0/install.rb:475:in `<main>'
install -c -p -m 755 /tmp/puppet-binfile20220305-50220-k1a6ye /wrkdirs/usr/ports/sysutils/puppet6/work/stage/usr/local/bin/puppet

• Error code 1

Stop.
make: stopped in /usr/ports/sysutils/puppet6

PR: 262518
With hat: puppet