DOC: Conda installation

[dhomeier]

Describe the bug
Is the installation procedure described on https://glueviz.readthedocs.io/en/stable/installation/conda.html still in any way relevant, in particular the install -c glueviz glueviz part? That channel never seems to have been updated beyond glue-core 1.2 and is probably broken entirely now, see also glue-viz/glue-standalone-apps#13 .
For comparison conda install -c conda-forge --update-all glue-core currently provides 1.17.1 among others (from miniforge/mambaforge, not sure how well this works out of a full anaconda installation).

[jfoster17]

I'm 99% sure that we should purge all references to the glueviz channel from our documentation and just recommend that people get glue from the conda-forge channel.

[astrofrog]

Yes this is correct, we should no longer use the glueviz channel