update to beaker 5

[rwaffen]

can we update this dependency pls?

beaker-hiera/beaker-hiera.gemspec

Line 33 in 2b8a2ac

s.add_runtime_dependency 'beaker', '~> 4.0'

we could run into problems otherwise

bundle install
Fetching gem metadata from https://rubygems.org/......
Resolving dependencies...
Could not find compatible versions

Because voxpupuli-acceptance >= 1.0.0 depends on beaker-hiera ~> 0.4
  and beaker-hiera >= 0.3.0 depends on beaker ~> 4.0,
  voxpupuli-acceptance >= 1.0.0 requires beaker ~> 4.0.
So, because Gemfile depends on voxpupuli-acceptance ~> 1.1
  and Gemfile depends on beaker ~> 5.0,
  version solving has failed.