LQR are only tested for squared (nx=nu) systems

The tests should be corrected to have NX and NU different.

mentioned in merge request !149 (merged)

I see two places where we use (DAM/AM)LQR for unit-test:

• test_rk4
• test_solvers

The former has been tackle in !149 (merged), the latter already uses non-squared LQR problems

I will close it (see !149 (merged)). Feel free to open it

closed

mentioned in commit 0e7d3b32