swap miniconda for mambaforge & mamba

changed milestone to %CSPP Geo Gridded GLM 1.0

assigned to @nickb

FYI rumor is that conda will be replaced by mamba internally in future versions. No idea on the timeline for that, but saw it pop up on twitter a couple weeks ago.

Yep I've seen that mentioned around the mamba github page!

This is more about replacing miniconda with miniforge to avoid any of our users running afoul of the new anaconda licensing. I think you've probably paid more attention to that news than I have. Any lingering concerns there?

No. I've talked with someone from Anaconda in a Pangeo community meeting and yeah as long as you don't pull any packages from the "defaults" channel then you are all good. Using miniconda is fine as long as modify your config to only look at conda-forge. The easiest way to do that, as you know, is to use miniforge/mambaforge. Their main concern is that they get compensated for all the work they do curating packages and testing that they work together.

merged

mentioned in commit b0c21d49