www/gitlab-ce: Allow run with rubygem-sidekiq6 6.5.12

• Bump PORTREVISION for package change

Note that it is an upstream issue.
Upstream has conflicting requirement for sidekiq which causes runtime issue.

from Gemfile:
gem 'sidekiq', '~> 6.5.7'

from lib/gitlab/patch/sidekiq_cron_poller.rb:
if Gem::Version.new(Sidekiq::VERSION) != Gem::Version.new('6.5.7')

raise 'New version of sidekiq detected, please remove or update this patch'

end