chore(autoware_internal_planning_msgs): unifiy module load srv

[yuki-takagi-66]

Description

Currently, behavior_velocity and motion_velocity depend on separate message definitions located at:

behavior_velocity: https://github.com/autowarefoundation/autoware_internal_msgs/blob/2c0323d64cc536cb1e70488349c853292b751ee0/autoware_internal_debug_msgs/srv/String.srv

motion_velocity: https://github.com/autowarefoundation/autoware_core/tree/1.3.0/planning/motion_velocity_planner/autoware_motion_velocity_planner/srv

We unify these by defining them within autoware_internal_planning_msgs.

How was this PR tested?

see core PR

Notes for reviewers

We have to merge by the following order

1. add new srv chore(autoware_internal_planning_msgs): unifiy module load srv #76
2. change to use new srv chore(motion_velocity_planner, behavior_velocity_planner): unifiy module load srv autoware_core#585
3. delete unused srv 0a45787

Effects on system behavior

None.

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 0.00%. Comparing base (a701d19) to head (2864a78).
Report is 59 commits behind head on main.

Additional details and impacted files

@@         Coverage Diff          @@
##            main   #76    +/-   ##
====================================
  Coverage   0.00%     0            
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  Files         12     0    -12     
  Lines        391     0   -391     
====================================
+ Misses       391     0   -391     

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