Reduce the poses used in PlanAndSaveTrajectory

`PlanMTC` has significantly reduced performance when called with
multiple `SetupMTCMoveToPose` stages and can no longer plan for as many
poses. Reducing the number of poses as a quick fix enables the
`PlanAndSaveTrajectory` objective to work again.

Author: dyackzan

src/lab_sim/objectives/create_pose_vector.xml

@@ -18,17 +18,6 @@
         vector="{target_poses}"
         input="{stamped_pose}"
       />
-      <Action
-        ID="CreateStampedPose"
-        orientation_xyzw="0;-1;0;0"
-        position_xyz="0.75;0.5;0.9"
-        stamped_pose="{stamped_pose}"
-      />
-      <Action
-        ID="AddPoseStampedToVector"
-        vector="{target_poses}"
-        input="{stamped_pose}"
-      />
       <Action
         ID="CreateStampedPose"
         orientation_xyzw="0;-1;0;0"
@@ -40,28 +29,6 @@
         vector="{target_poses}"
         input="{stamped_pose}"
       />
-      <Action
-        ID="CreateStampedPose"
-        orientation_xyzw="0;-1;0;0"
-        position_xyz="0.25;0.5;0.7"
-        stamped_pose="{stamped_pose}"
-      />
-      <Action
-        ID="AddPoseStampedToVector"
-        vector="{target_poses}"
-        input="{stamped_pose}"
-      />
-      <Action
-        ID="CreateStampedPose"
-        orientation_xyzw="0;-1;0;0"
-        position_xyz="0;0.5;0.6"
-        stamped_pose="{stamped_pose}"
-      />
-      <Action
-        ID="AddPoseStampedToVector"
-        vector="{target_poses}"
-        input="{stamped_pose}"
-      />
       <Action
         ID="CreateStampedPose"
         orientation_xyzw="0;-1;0;0"
@@ -73,28 +40,6 @@
         vector="{target_poses}"
         input="{stamped_pose}"
       />
-      <Action
-        ID="CreateStampedPose"
-        orientation_xyzw="0;-1;0;0"
-        position_xyz="-0.5;0.5;0.8"
-        stamped_pose="{stamped_pose}"
-      />
-      <Action
-        ID="AddPoseStampedToVector"
-        vector="{target_poses}"
-        input="{stamped_pose}"
-      />
-      <Action
-        ID="CreateStampedPose"
-        orientation_xyzw="0;-1;0;0"
-        position_xyz="-0.75;0.5;0.9"
-        stamped_pose="{stamped_pose}"
-      />
-      <Action
-        ID="AddPoseStampedToVector"
-        vector="{target_poses}"
-        input="{stamped_pose}"
-      />
       <Action
         ID="CreateStampedPose"
         orientation_xyzw="0;-1;0;0"