Update src/pymor/models/symplectic.py

Remove comment
Co-authored-by: Stephan Rave <stephanrave@uni-muenster.de>

src/pymor/models/symplectic.py

@@ -53,7 +53,6 @@ class QuadraticHamiltonianModel(InstationaryModel):
         If time_stepper is `None` and nt is specified, the
         :class:`implicit midpoint rule <pymor.algorithms.timestepping.ImplicitMidpointTimeStepper>`
         as time_stepper.
-        If time_stepper is not 'None', the parameter nt is ignored.
     num_values
         The number of returned vectors of the solution trajectory. If `None`, each
         intermediate vector that is calculated is returned.