message: do not check forces on melodic
diff: @@ -87,11 +87,13 @@ TEST_P(GripperGraspFixtureTest, CanGrasp) { // NOLINT(cert-err58-cpp)
  updateFingerState();
  EXPECT_NEAR(finger_1_pos * 2, kStoneWidth, kAllowedPositionError);
  EXPECT_NEAR(finger_2_pos, finger_1_pos, kAllowedPositionError);
  + if (ROS_VERSION_MINIMUM(1, 15, 0)) { // only test forces in noetic and later versions
  double expected_force = desired_force / 2.0;
  EXPECT_NEAR(finger_1_force, expected_force, kAllowedForceError);
  EXPECT_NEAR(finger_2_force, expected_force, kAllowedForceError);
  }
  }
  +}
  TEST_P(GripperFailGraspFixtureTest, CanFailGrasp) { // NOLINT(cert-err58-cpp)
  double start_width = 0.08;
  