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 🤷

[Sharpie]

Last I worked on it (which was a decade ago) puppet strings was very focused on documenting Classes and Defined Types.

If that is still the case, then puppet doc is the only tool that can generate references for things like Native Types and Functions.