[docs] [android] retrieve the app lib name dynamically in Kotlin

[IT-ess]

Hi !

First, thank you for this whole project.

I'm building a plugin that calls some Rust methods as explained in this section of the docs. It works as intended, except that the lib name to load is not dynamic at all.

We should provide a way for plugin writers to retrieve the name of the generated lib by rust (I didn't find myself how to do this). Otherwise plugins that rely on this feature are not really plugin, since they require changing manually the name of the lib to link.

If someone knows a workaround, I would be happy to open a PR to document this case.

[IT-ess]

For the record, I tried to pass the lib name through plugin configuration, without success.

[Subham-KRLX]

@IT-ess i would like to fix this issue, raising pr regarding this soon.