Remove unused mjOption.apirate.

PiperOrigin-RevId: 815633571
Change-Id: Ib98f3eb2df47f96fa1fe6e987a3a0cd23a9479f6

mjx/mujoco/mjx/_src/io_test.py

@@ -173,7 +173,7 @@ class ModelIOTest(parameterized.TestCase):
       self.assertFalse(hasattr(mx, 'bvh_aabb'))
     elif impl == 'c':
       # Options specific to C are populated.
-      self.assertEqual(mx.opt._impl.apirate, m.opt.apirate)
+      self.assertEqual(mx.opt._impl.noslip_iterations, m.opt.noslip_iterations)
       # Fields private to C backend impl are populated.
       self.assertTrue(hasattr(mx._impl, 'bvh_aabb'))
     elif impl == 'warp':

mjx/mujoco/mjx/_src/types.py

@@ -497,7 +497,6 @@ class OptionC(PyTreeNode):
   disableactuator: int
   sdf_initpoints: int
   has_fluid_params: bool
-  apirate: jax.Array
   noslip_tolerance: jax.Array
   ccd_tolerance: jax.Array
   noslip_iterations: int