Update Miniconda references to Miniforge in HPC docs

[tomvothecoder]

Description

• Closes [Doc]: Update Miniconda references to Miniforge on "xCDAT on Jupyter and HPC Machines" page #728
• Add clean-docs command to Makefile
• Delete unused prefix from conda env yml files

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules

If applicable:

• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass with my changes (locally and CI/CD build)
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have noted that this is a breaking change for a major release (fix or feature that would cause existing functionality to not work as expected)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (84e4a3f) to head (8fd2a3f).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #731   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           15        15           
  Lines         1621      1621           
=========================================
  Hits          1621      1621           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.