Clean up Servo initial_positions files

[AndyZe]

Description

Specification of initial_velocities isn't necessary. Compare against: https://github.com/ros-planning/moveit_resources/blob/ros2/panda_moveit_config/config/initial_positions.yaml

[codecov]

Codecov Report

Merging #1282 (40b35a5) into main (6288b0d) will decrease coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1282      +/-   ##
==========================================
- Coverage   61.48%   61.45%   -0.02%     
==========================================
  Files         274      274              
  Lines       24940    24940              
==========================================
- Hits        15332    15325       -7     
- Misses       9608     9615       +7     

Impacted Files	Coverage Δ
...dl_kinematics_plugin/src/kdl_kinematics_plugin.cpp	75.36% <0.00%> (-1.07%)	⬇️
...nning_scene_monitor/src/planning_scene_monitor.cpp	45.29% <0.00%> (-0.43%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 6288b0d...40b35a5. Read the comment docs.

[AndyZe]

Closing in favor of #1283