Add coordinate converters between MNI152 and FSAverage

[gavinmischler]

Reference Issues/PRs

What does this implement/fix? Explain your changes.

Adds functions to convert between MNI152 space and fsaverage space

Any other comments?

[codecov]

Codecov Report

Attention: Patch coverage is 38.46154% with 8 lines in your changes missing coverage. Please review.

Project coverage is 73.64%. Comparing base (8be3445) to head (60742e1).
Report is 11 commits behind head on main.

Files with missing lines	Patch %	Lines
naplib/localization/coordinate_conversions.py	27.27%	8 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #212      +/-   ##
==========================================
- Coverage   74.03%   73.64%   -0.40%     
==========================================
  Files          58       59       +1     
  Lines        4287     4398     +111     
==========================================
+ Hits         3174     3239      +65     
- Misses       1113     1159      +46     

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