Windows test updates

[aburrell]

Description

Fixes #105 by using filecmp with the Windows unit tests. Also tested the remaining Windows-specific logic, but that is still necessary. Updated the NASA CDF installation to the latest version.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Running unit tests locally and on CI.

Test Configuration:

• Operating system: GitHub Actions and OS X Big Sur
• Version number: Python 3.8
• Any details about your local setup that are relevant: also tested against https://github.com/lkilcommons/ssj_auroral_boundary/pull/13 to fix the DMSP SSJ failures.

Checklist:

• [x] Make sure you are merging into the develop (not main) branch
• [x] My commits are formatted appropriately (following the SciPy/NumPy style)
• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] New and existing unit tests pass locally with my changes
• [x] Any dependent changes have been merged and published in downstream modules
• [x] Add a note to Changelog.rst, summarising the changes
• [x] Add yourself to AUTHORS.rst

[coveralls]

Coverage increased (+0.5%) to 82.125% when pulling be5624986628ae2f2f6ce67822e85cbf17ac9b3d on windows_test_updates into 347b87044f22c725571c8d11f347ee7ee91449e4 on develop.