feat: post-fit Asimov data generation

[alexander-held]

Extending the model_utils.asimov_data API to allow feeding in a FitResults object to create post-fit Asimov datasets (with auxiliary data set to the best-fit values, such that subsequent fits to that dataset reproduce the best-fit values used to create the dataset). New poi_name and poi_value keyword arguments allow setting a POI to a specific value.

* model_utils.asimov_data supports post-fit Asimov dataset generation via new keyword argument fit_results
* added support for custom POI values in Asimov dataset generation
* updated pre-commit

[codecov[bot]]

Codecov Report

Base: 100.00% // Head: 100.00% // No change to project coverage :thumbsup:

Coverage data is based on head (327fab4) compared to base (1e865c3). Patch coverage: 100.00% of modified lines in pull request are covered.

Additional details and impacted files

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