MNT: Update of docstring in test_flight_3dof.py

- MNT: correction of docstring now that fixtures are used.

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: aZira371

tests/integration/simulation/test_flight_3dof.py

@@ -265,10 +265,8 @@ def test_weathercock_aligned_no_evolution(flight_weathercock_pos):
 
     Parameters
     ----------
-    example_plain_env : rocketpy.Environment
-        A basic environment fixture for flight simulation.
-    point_mass_rocket : rocketpy.PointMassRocket
-        A point mass rocket fixture for 3-DOF simulation.
+    flight_weathercock_pos : rocketpy.Flight
+        A Flight fixture configured for weathercocking tests with a nonzero initial angle.
     """
     flight = flight_weathercock_pos
     # Body pointing in +x direction (into the wind for vx=50)