FIM added for PyBOP likelihood functions

[Dibyendu-IITKGP]

Description

Compute the observed Fisher Information Matrix (FIM) for the given inputs. The FIM is computed using the square of the gradient, divided by the number of data points.

Issue reference

Fixes #630

Review

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.25%. Comparing base (9df5000) to head (4f17323).
Report is 11 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #632      +/-   ##
===========================================
+ Coverage    99.22%   99.25%   +0.02%     
===========================================
  Files           62       63       +1     
  Lines         4536     4686     +150     
===========================================
+ Hits          4501     4651     +150     
  Misses          35       35              

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[BradyPlanden]

This is looking great @Dibyendu-IITKGP — a few comments to think about!

[BradyPlanden]

LGTM - thanks @Dibyendu-IITKGP!