[Tests] Factorize code and add new tests on adding/removing triangles in TriangleSetTopology_test

[epernod]

1 issue to be created:
Test testAddingTriangles reveal that method
testAddingTriangles is crashing. Check:

    // TODO @epernod (2025-01-28): Adding the triangle create a segmentation fault. Need to investigate why
    // triangleModifier->addTriangles(triangesToAdd);

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[epernod]

[ci-build][with-all-tests]

[bakpaul]

Nice work on tests.
While you where at it, have you though about the two problems raised by this issue ? #5127
It seems that the interaction between topological changes and some forcefield are not properly working. MAybe the way they are propagated ? Do you have an idea ?