Add Interpolate to Joint State objective XML (#15)

Co-authored-by: Abishalini <abishalini.sivaraman@picknik.ai>

src/picknik_ur_base_config/objectives/interpolate_to_joint_state.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0"?>
+<root BTCPP_format="4" main_tree_to_execute="Interpolate to Joint State">
+    <BehaviorTree ID="Interpolate to Joint State" _description="Move to a specified joint state">
+        <Sequence name="root">
+            <SubTree ID="InterpolateToJointStateWaypoint" target_joint_state="{interpolate_to_joint_state.target_joint_state}"/>
+        </Sequence>
+    </BehaviorTree>
+    <BehaviorTree ID="InterpolateToJointStateWaypoint">
+        <Sequence name="interpolate_to_waypoint_main">
+            <Action ID="InitializeMTCTask" task_id="interpolate_to_joint_state" controller_names="/joint_trajectory_controller /robotiq_gripper_controller" task="{interpolate_to_waypoint_task}"/>
+            <Action ID="SetupMTCCurrentState" task="{interpolate_to_waypoint_task}"/>
+            <Action ID="SetupMTCInterpolateToJointState" joint_state="{target_joint_state}" name="SetupMTCInterpolateToJointState_First" planning_group_name="manipulator" task="{interpolate_to_waypoint_task}"/>
+            <Action ID="PlanMTCTask" solution="{interpolate_to_waypoint_solution}" task="{interpolate_to_waypoint_task}"/>
+            <Action ID="ExecuteMTCTask" solution="{interpolate_to_waypoint_solution}"/>
+        </Sequence>
+    </BehaviorTree>
+</root>