Update the nonholonomic equation of motion chapter

[moorepants]

Minor update for this chapter.

[github-actions]

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[Peter230655]

Below the heading Numerical Evaluation is a Warning.

There you write:
sym_mat = sm.Matrix([[a, b], [c, d]])
eval_sym_mat = sm.lambdify((a, b, c, d), sym_mat)
num_mat = eval_sym_mat(1.0, 2.0, 3.0, 4.0)
num_mat

Would it make sense to add cse=True?
I guess with this example it does not matter, but I think, 50% of my examples would take 'forever' to integrate without this.

[moorepants]

That is a different chapter than this, but I think I should use cse=True in all lambdify calls after the SymPy chapter (where I originally introduce lambdify).

[Peter230655]

Sorry, I still get confused, where to comment!