Update waveguide inlet boundary

[OresteMarquis]

Description

In the time-harmonic Maxwell solver, when using the waveguide inlet boundary and defining a left-handed basis of vector by the 4 points creating the quadrilateral of the mesh the resulting computed excitation field was wrong.

Solution

Instead of only flipping the two basis vector (which led to erroneous calculation), we perform all the computation in the local reference and apply a rotation matrix to revert the solution to the global reference frame.

Testing

This has been tested by the unit test the unit tests have been updated to test this new orientation.

Documentation

No new documentation.

Miscellaneous (will be removed when merged)

Checklist (will be removed when merged)

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Code related list:

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• Fix has unit test(s) (preferred) or application test(s), and restart files are in the generator folder
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