Updated instructions for setup.md

[kristi-sara]

Mac OS Remove Kyngchaos link for macos, it no longer supports gdal. updated homebrew instructions for mac to match instruction from sf package -> no longer need proj or geos.

I believe with terra, tidyverse, sf, the utilities that used to be covered by kyngchaos is no longer needed and it is reflected on their website when you go to the link: https://www.kyngchaos.com/software/

R version Also updated the r version from 3.xxx to 4.xxx in r-downloads

In response to: https://github.com/datacarpentry/geospatial-workshop/issues/69

[github-actions[bot]]

:ok: Pre-flight checks passed :smiley:

This pull request has been checked and contains no modified workflow files, spoofing, or invalid commits.

It should be safe to Approve and Run the workflows that need maintainer approval.