Avoid using the default conda channel?

[emlys]

Recent versions of mamba have started to show this warning:

  warning  libmamba 'repo.anaconda.com', a commercial channel hosted by Anaconda.com, is used.
      
  warning  libmamba Please make sure you understand Anaconda Terms of Services.
      
  warning  libmamba See: https://legal.anaconda.com/policies/en/

Though we usually use the -c conda-forge option, this only adds the conda-forge channel, it does not remove the defaults. To ensure that only conda-forge is used, you can do --override-channels -c conda-forge. If all our dependencies are indeed available on conda-forge, this might be worth doing to (1) get rid of the warning and (2) not risk violating Anaconda's terms of service. I can imagine this could be an issue if, for example, we redistribute a package from Anaconda in our binaries, and then someone wants to use invest for a commercial purpose.