feat(protocol-designer): emit Python for dispense command

[ddcc4]

Overview

This generates the Python code for the PD atomic dispense command. AUTH-1094

As with the aspirate command, for the dispense(rate=...), we have to emit a literal division expression in the Python code because the PAPI takes a ratio, and we don't know what the PAPI default flow rate for the pipette is.

Test Plan and Hands on Testing

Added unit tests.

I also took the generated Python and used simulate to confirm that it's well-formed.

Review requests

The JSON command has a { meta: { isAirGap } } to indicate that we're dispensing air. There is no corresponding way to indicate that in the Python API. So we're supposed to just use the dispense() API for both liquid and air, right?

Risk assessment

Low. Python code generation is not used externally yet.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 25.71%. Comparing base (1bcbccb) to head (459a4d8).

Additional details and impacted files

@@           Coverage Diff           @@
##             edge   #17601   +/-   ##
=======================================
  Coverage   25.70%   25.71%           
=======================================
  Files        2843     2843           
  Lines      218884   218900   +16     
  Branches    17947    17949    +2     
=======================================
+ Hits        56268    56284   +16     
  Misses     162601   162601           
  Partials       15       15           

Flag	Coverage Δ
protocol-designer	18.96% <100.00%> (+<0.01%)	⬆️
step-generation	4.38% <100.00%> (+<0.01%)	⬆️

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

Files with missing lines	Coverage Δ
...-generation/src/commandCreators/atomic/dispense.ts	86.82% <100.00%> (+1.03%)	⬆️

... and 1 file with indirect coverage changes

[ncdiehl11]

this LGTM