Replace `puppet doc` calls with openvox-strings

[jay7x]

puppet doc is called in lib/puppet_references/doc_command.rb (PuppetReferences::DocCommand). This should be replaced with openvox-strings call.

See OpenVoxProject/openvox#330 for more details about puppet doc deprecation.

[jay7x]

See lib/puppet_references/puppet/puppet_doc.rb for the actual call

[binford2k]

or we un-deprecate puppet doc 🤷