fix: Specify column dtypes in dataset definitions

[dkrako]

Description

As discussed in today's meeting, #517 probably comes from lots of na-rows in the beginning of a file and faulty inferrence of the column datatype.

Hopefully fixes issue #517

Implemented changes

• Specify column dtypes in all public datasets

Type of change

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

How Has This Been Tested?

No additional tests written.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings

[codecov]

Codecov Report

All modified lines are covered by tests ✅

Comparison is base (78b649c) 100.00% compared to head (500dfe4) 100.00%.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #593   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           52        52           
  Lines         2331      2337    +6     
  Branches       581       582    +1     
=========================================
+ Hits          2331      2337    +6     

Files	Coverage Δ
src/pymovements/datasets/gazebase.py	100.00% <100.00%> (ø)
src/pymovements/datasets/gazebasevr.py	100.00% <100.00%> (ø)
src/pymovements/datasets/hbn.py	100.00% <ø> (ø)
src/pymovements/datasets/judo1000.py	100.00% <100.00%> (ø)
src/pymovements/datasets/sb_sat.py	100.00% <ø> (ø)
src/pymovements/datasets/toy_dataset.py	100.00% <100.00%> (ø)

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[dkrako]

#591 has shown that this PR effectively resolves #517

[dkrako]

@prassepaul @SiQube
this is ready for review and resolves the bug in #517