Removed unnecessary unit conversion in the rotation phase update code

src/swiftest/swiftest_drift.f90

@@ -593,12 +593,7 @@ module subroutine swiftest_drift_cb_rotphase_update(self, param, dt)
       class(swiftest_parameters),   intent(in)    :: param  !! Current run configuration parameters 
       real(DP),                     intent(in)    :: dt     !! Stepsize
 
-      ! Internals
-      real(DP) :: rotmag
-
-      rotmag = (.mag. self%rot(:)) * dt * param%TU2S
-
-      self%rotphase = MOD(self%rotphase + rotmag, 2 * PI) ! phase angle calculated in radians and then scaled by 2pi to be unitless
+      self%rotphase = MOD(self%rotphase + (.mag. self%rot(:)) * dt , 2 * PI) ! phase angle calculated in radians and then scaled by 2pi to be unitless
 
    end subroutine swiftest_drift_cb_rotphase_update