TST: FinFlutterAnalysis not working properly?

[Gui-FernandesBR]

Is your feature request related to a problem? Please describe.

We recently faced a problem with the unit tests regarding the fin flutter analysis. The problem was temporary fixed by deleting the test that was breaking every time (#366).

Similar link already mentioned in the above PR: https://stackoverflow.com/questions/38228088/same-python-code-same-data-different-results-on-different-machines

Describe the solution you'd like

A test that cover all the fin-flutter features already implemented, and actually works in different machines and operational systems.

[Gui-FernandesBR]

Suggestion: try to update pytest version in the tests

[Gui-FernandesBR]

So, the problem is actually related to scipy's integrator, which has been throwing different results for the same simulations across different operational systems.

A further investigation is still necessary here, it is letting some of our unit tests not so powerful, since we have to increase relative and absolute errors for some tests in order to pass through github actions