mod_constants: Decrease max_it
mod_constants: Decrease max_it

It was increased in d54ebb96de3851cf1121dbee6fddecfb1b2dc0bc instead of
n_iterations, and wasn’t fixed in
27ba35d46da86f821048e74279dacc9f2c0c6275.

This leaded to enormous computation time needed for s_curve.

M2-AAIS/BAD