Panelled arc wise scaling fator

[kimonito98]

Added arc-wise panelled scaling factor as estimatable parameters (parallel & perpendicular to source). Note: given that PaneledRadiationPressureTargetModel did NOT contain references to the scaling, I hat to adapt it, similar to the cannonball version.
Tested fixed relevant unitTestAccelerationPartials.cpp.

[DominicDirkx]

Thanks for adding this PR! I'll do my best to have a look at it before the Christmas break :)

[DominicDirkx]

I see the CI is failing with this error:

58/290 Test #46: test_electromagnetism_RadiationPressureAcceleration ..................***Failed 3.12 sec
Running 9 test cases...
unknown location(0): fatal error: in "test_radiation_pressure_acceleration/testRadiationPressureAcceleration_DynamicallyPanelunitestradedSource_CannonballTarget_LAGEOS": class std::runtime_error: Error: Target model is not a PaneledRadiationPressureTargetModel
D:\a\tudat\tudat\tests\src\astro\electromagnetism\unitTestRadiationPressureAcceleration.cpp(1283): last checkpoint

before diving into it, could you check whether this test works properly on your system?

Good news is all other tests pass!