Add optuna option for searchers

[fraimondo]

Integrate Optuna (https://optuna.org/) for Hyperparameter Tuning as optuna searcher, using the OptunaSearchCV model.

[codecov]

Codecov Report

Attention: Patch coverage is 81.25000% with 15 lines in your changes are missing coverage. Please review.

Project coverage is 90.13%. Comparing base (dbdbbfc) to head (721d8e6).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #262      +/-   ##
==========================================
- Coverage   90.40%   90.13%   -0.27%     
==========================================
  Files          53       54       +1     
  Lines        2344     2423      +79     
  Branches      471      491      +20     
==========================================
+ Hits         2119     2184      +65     
- Misses        147      157      +10     
- Partials       78       82       +4     

Flag	Coverage Δ
docs	100.00% <ø> (ø)
julearn	90.13% <81.25%> (-0.27%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
docs/conf.py	100.00% <ø> (ø)
julearn/api.py	95.17% <ø> (ø)
julearn/conftest.py	93.10% <100.00%> (+0.24%)	⬆️
julearn/model_selection/__init__.py	100.00% <100.00%> (ø)
julearn/model_selection/_skopt_searcher.py	77.14% <87.50%> (+22.59%)	⬆️
julearn/pipeline/pipeline_creator.py	87.24% <54.54%> (-0.84%)	⬇️
julearn/model_selection/_optuna_searcher.py	82.50% <82.50%> (ø)

[github-actions]

PR Preview Action v1.4.7
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2024-05-03 14:57 UTC

[synchon]

The PR also needs a description for future reference.