refactor(api): improve labware movement code

[sanni-t]

Overview

Last refactoring (ish) PR before I add the contextual gripper offsets. This makes updating the code much easier!

Test Plan

• Test on a robot- even better, mimic labware movements from the science protocols on the robot to make sure everything still works correctly.

Changelog

• compartmentalizes the labware movement code to make it easier to test
• the only functional change is removal of the gripper Z-home commands before each move_to to the gripper Z home position. See RLAB-215 for more info. With RLAB-211 fixed, there doesn't seem to be a need to issue a home command before moving to gripper Z each time

Review requests

• Mainly just- does the refactor make sense? any other improvements I should make?
• I have tried to preserve tests as is so that I can catch any unintended changes. Caught one outdated value in the tests that we were just not using so that's good and is reassuring that tests work
• @ahiuchingau do you think removing any of the homes before the move to gripper Z home position cause any issues?

Risk assessment

Low since tests

[codecov]

Codecov Report

Merging #13174 (369358d) into internal-release_0.14.0 (57b7c9b) will increase coverage by 0.05%.
Report is 5 commits behind head on internal-release_0.14.0.
The diff coverage is n/a.

@@                     Coverage Diff                     @@
##           internal-release_0.14.0   #13174      +/-   ##
===========================================================
+ Coverage                    72.53%   72.59%   +0.05%     
===========================================================
  Files                         2359     2372      +13     
  Lines                        64994    65408     +414     
  Branches                      7213     7209       -4     
===========================================================
+ Hits                         47143    47482     +339     
- Misses                       16105    16181      +76     
+ Partials                      1746     1745       -1     

Flag	Coverage Δ
g-code-testing	96.44% <ø> (ø)
notify-server	89.13% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
api/src/opentrons/motion_planning/__init__.py	100.00% <ø> (ø)
api/src/opentrons/motion_planning/types.py	100.00% <ø> (ø)
api/src/opentrons/motion_planning/waypoints.py	100.00% <ø> (ø)
...rc/opentrons/protocol_engine/execution/movement.py	100.00% <ø> (ø)
...pi/src/opentrons/protocol_engine/state/geometry.py	100.00% <ø> (ø)
api/src/opentrons/protocol_engine/types.py	97.56% <ø> (-0.10%)	⬇️

... and 15 files with indirect coverage changes

[ahiuchingau]

Makes sense to me!

I think removing the home commands should be fine

[SyntaxColoring]

Code looks good to me. Discussed in-person: we'll QA the home() vs. move_to() thing.

[sanni-t]

Tested moving labware between all modules and deck on a QA bot and it worked exactly the same as before the change.