Push releases to Anaconda Cloud

[bschilder]

It might be a nice extra feature to be able to upload your R package to Anaconda Cloud at the end of a successful GHA run.

For Bioc packages

One of the current issues with bioconda is that the Bioc R packages get updated pretty infrequently. It also means that neither Bioc (who is totally separate from the bioconda team, thought does have some communication with them) nor the developer of the Bioc package

For CRAN packages

Not sure if there's regular automated updates to CRAN packages on Anaconda Cloud. But if not, this could be another use case.

For non Bioc/CRAN packages

This could be especially useful for making more non-Bioc/CRAN packages available for conda environments via Anaconda Cloud.

This could be synced with the GH Releases mentioned here: #80