fix: Delegate checks exact compatibility of signatures

[paulgessinger]

As described in #1140, signatures are not checked for exact compatibility by Delegate.

This PR introduces an additional check where it will try to assign a given callable to an expected function pointer type generated from the signature given to Delegate. This assignment only succeeds if the signatures match exactly. This is enforced by a static_assert.

Fixes #1140

/cc @Corentin-Allaire

[codecov]

Codecov Report

Merging #1141 (47cba3e) into main (787658a) will decrease coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1141      +/-   ##
==========================================
- Coverage   48.17%   48.16%   -0.01%     
==========================================
  Files         341      341              
  Lines       17649    17646       -3     
  Branches     8327     8327              
==========================================
- Hits         8502     8499       -3     
  Misses       3372     3372              
  Partials     5775     5775              

Impacted Files	Coverage Δ
Core/include/Acts/TrackFitting/KalmanFitter.hpp	38.09% <ø> (-0.37%)	⬇️
.../Acts/TrackFitting/detail/VoidKalmanComponents.hpp	25.00% <ø> (ø)
Core/include/Acts/Utilities/Delegate.hpp	80.95% <ø> (ø)
...de/Acts/TrackFinding/CombinatorialKalmanFilter.hpp	33.06% <0.00%> (-0.18%)	⬇️

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[Corentin-Allaire]

Looks good to me ! It is great that we will be able avoid thing similar to issue #1140 in future