Rename grasp parameter 'max_force' to 'force'.

franka_gripper/action/Grasp.action

 float64 width    # [m]
 float64 speed    # [m/s]
-float64 max_force  # [N]
+float64 force  # [N]
 ---
 bool success
 string error

franka_gripper/src/franka_gripper.cpp

@@ -75,7 +75,7 @@ bool stop(const franka::Gripper& gripper, const StopGoalConstPtr& /*goal*/) {
 }
 
 bool grasp(const franka::Gripper& gripper, const GraspGoalConstPtr& goal) {
-  return gripper.grasp(goal->width, goal->speed, goal->max_force);
+  return gripper.grasp(goal->width, goal->speed, goal->force);
 }
 
 }  // namespace franka_gripper