Fix namespace references in Pick & Place tutorial

tutorials/pick_and_place/PickAndPlaceProject/Packages/manifest.json

     "com.unity.ide.rider": "2.0.7",
     "com.unity.ide.visualstudio": "2.0.3",
     "com.unity.ide.vscode": "1.2.2",
+    "com.unity.robotics.ros-tcp-connector": "https://github.com/Unity-Technologies/ROS-TCP-Connector.git?path=/com.unity.robotics.ros-tcp-connector#0b7ddbf36a13fbd47a0aeead062f0f57271b7e96",
-    "com.unity.robotics.ros-tcp-connector": "https://github.com/Unity-Technologies/ROS-TCP-Connector.git#v0.1.2",
     "com.unity.test-framework": "1.1.18",
     "com.unity.textmeshpro": "3.0.1",
     "com.unity.timeline": "1.4.3",

tutorials/pick_and_place/Scripts/SourceDestinationPublisher.cs

-using RosMessageTypes.Geometry;
-using ROSGeometry;
-using Quaternion = UnityEngine.Quaternion;
+using Unity.Robotics.ROSTCPConnector;
+using Unity.Robotics.ROSTCPConnector.ROSGeometry;
 
 public class SourceDestinationPublisher : MonoBehaviour
 {

tutorials/pick_and_place/Scripts/TrajectoryPlanner.cs

 using System.Collections;
 using System.Linq;
-using RosMessageTypes.Geometry;
-
-using ROSGeometry;
-using Quaternion = UnityEngine.Quaternion;
-using RosImage = RosMessageTypes.Sensor.Image;
-using Transform = UnityEngine.Transform;
-using Vector3 = UnityEngine.Vector3;
+using Unity.Robotics.ROSTCPConnector;
+using Unity.Robotics.ROSTCPConnector.ROSGeometry;
 
 
 public class TrajectoryPlanner : MonoBehaviour