Update documentation for QueueAdapters::lookup

[davydovanton]

I added simple documentation for method and also added :nodoc: because this method called only in private QueueAdapter::interpret_adapter.

/cc @kaspth

[kaspth]

I'm not sure about nodoc'ing it. While it's true it's only used one place internally, other people might use it in their apps because it's been public API.

Also with the nodoc people will only see the comment right next to the implementation and I feel like that's communicative enough in and of itself.
But ¯_(ツ)_/¯, what do you think @chancancode @rafaelfranca?

[senny]

Agree with @kaspth either we :nodoc: it but then we don't need the comment (code is pretty clear) or we add the comment for the public API.

[davydovanton]

@kaspth, @senny I agree with you, and I deleted nodoc

[kaspth]

Let's add an example too, since now people don't have the implementation next to them.

[davydovanton]

@kaspth added simple example for this method. What do you think?

[senny]

I don't think the variable assignment is necessary

[davydovanton]

@kaspth @senny updated all 😅

[senny]

Thank you 💛

[davydovanton]

@senny @kaspth thank you for review my PR 🎉 🌟 🎉

[kaspth]

@davydovanton Nice ❤️