maint: Handle environment vars in micromamba/tests with monkeypatch

[holzman]

Description

Addresses #3830.

Nearly all of places where environment variables were set in the tests were needed, so I didn't change very much.

Type of Change

• Bugfix
• Feature / enhancement
• CI / Documentation
• Maintenance

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 63.58%. Comparing base (6f11ca2) to head (b71842e).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3988   +/-   ##
=======================================
  Coverage   63.57%   63.58%           
=======================================
  Files         315      315           
  Lines       38562    38562           
  Branches     2950     2950           
=======================================
+ Hits        24517    24519    +2     
+ Misses      13976    13974    -2     
  Partials       69       69           

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[holzman]

Weird, I must have broken something that worked for me locally. I'll take a look next week.

[holzman]

Oh, not my fault!

test_update.py::TestUpdateConfig::test_target_prefix_with_no_settings should have always been failing. It was only succeeding because MAMBA_ROOT_PREFIX was altered by earlier tests as a side effect.