feat: Add Discontinuous Galerkin (DG) discretization on Bernstein-Bézier tetrahedra and apply it to the acoustic wave propagator via SIPDG (Symmetric Interior Penalty DG)

[sframba]

• Create BB_Tetrahedron element and all matrices needed for IPDG acoustic 2nd order wave propagator
• Cleanup BB_Tetrahedron element
• Add new discretization formulation and corresponding dispatch
• Create AcousticWavePropagationDG solver
• Add and test mass, stiffness, damping, penalty and flux matrices
• (optional) Finalize basis element for other solvers, adding the needed matrices (e.g., anisotropic stiffness, ...)
• (optional) Create SIPDG version of other 2nd order wave propagators

[codecov]

Codecov Report

Attention: Patch coverage is 2.10657% with 790 lines in your changes missing coverage. Please review.

Project coverage is 57.21%. Comparing base (672d300) to head (5a8e39a).

Files with missing lines	Patch %	Lines
...econdOrderEqn/isotropic/AcousticWaveEquationDG.cpp	0.00%	290 Missing ⚠️
...niteElement/elementFormulations/BB_Tetrahedron.hpp	0.00%	248 Missing ⚠️
...rderEqn/isotropic/AcousticWaveEquationDGKernel.hpp	0.00%	198 Missing ⚠️
...Solvers/wavePropagation/shared/WaveSolverUtils.hpp	25.58%	32 Missing ⚠️
...ropagation/dg/acoustic/shared/AcousticFieldsDG.hpp	0.00%	10 Missing ⚠️
...ents/finiteElement/FiniteElementDiscretization.cpp	0.00%	8 Missing ⚠️
...econdOrderEqn/isotropic/AcousticWaveEquationDG.hpp	20.00%	4 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #3432      +/-   ##
===========================================
- Coverage    57.63%   57.21%   -0.42%     
===========================================
  Files         1238     1243       +5     
  Lines       107143   107934     +791     
===========================================
+ Hits         61750    61755       +5     
- Misses       45393    46179     +786     

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