FEA Implement pruning using honest subsample data to fit the leaves

[adam2392]

Changes proposed in this pull request:

• Adds honest pruning, so no empty leaves occur within the HonestTreeClassifier

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[codecov]

Codecov Report

Attention: Patch coverage is 82.97872% with 8 lines in your changes missing coverage. Please review.

Project coverage is 80.11%. Comparing base (1d970b0) to head (a2bdf39).
Report is 1 commits behind head on main.

Files	Patch %	Lines
treeple/tree/_honest_tree.py	82.60%	3 Missing and 5 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #286      +/-   ##
==========================================
+ Coverage   80.00%   80.11%   +0.10%     
==========================================
  Files          24       24              
  Lines        2221     2258      +37     
  Branches      411      418       +7     
==========================================
+ Hits         1777     1809      +32     
- Misses        312      313       +1     
- Partials      132      136       +4     

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