Rust/Go packages license issues

A typical rust package use dozens of packages which have different licenses and requirements. A rust package and its dependencies are usually compiled into one library or executable.
For eg: https://github.com/conda-forge/staged-recipes/pull/11315 has a rust package with 91 dependencies with various MIT/BSD-3-Clause/Apache-2.0 licenses and maybe others.

This implies that the licenses and copyrights of the dependencies need to be distributed with the package. There are some tools to help do this like https://github.com/maghoff/cargo-license-hound, https://github.com/onur/cargo-license.

I'm opening this issue so that @conda-forge/staged-recipes and @conda-forge/core know about this when reviewing Rust recipes.

cc @andfoy, @mingwandroid