Add deps to pre-commit mypy and fix issues

[tomvothecoder]

Description

• Closes [FEATURE]: Add dependencies to pre-commit mypy hook and fix issues #190

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-commenter]

Codecov Report

Merging #191 (27075ab) into main (201a575) will decrease coverage by 0.47%.
The diff coverage is 97.93%.

@@             Coverage Diff             @@
##              main     #191      +/-   ##
===========================================
- Coverage   100.00%   99.52%   -0.48%     
===========================================
  Files            8        8              
  Lines          381      421      +40     
===========================================
+ Hits           381      419      +38     
- Misses           0        2       +2     

Impacted Files	Coverage Δ
xcdat/spatial_avg.py	98.86% <91.66%> (-1.14%)	⬇️
xcdat/__init__.py	100.00% <100.00%> (ø)
xcdat/axis.py	100.00% <100.00%> (ø)
xcdat/bounds.py	100.00% <100.00%> (ø)
xcdat/dataset.py	100.00% <100.00%> (ø)
xcdat/xcdat.py	100.00% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update b71f466...27075ab. Read the comment docs.