Improve docker file

[spenserblack]

Separates the build image from the runner image.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 73.70%. Comparing base (8418ce0) to head (d079453).
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #470   +/-   ##
=======================================
  Coverage   73.70%   73.70%           
=======================================
  Files          18       18           
  Lines         502      502           
=======================================
  Hits          370      370           
  Misses        132      132           

Flag	Coverage Δ
--no-default-features	72.52% <ø> (ø)
--no-default-features --features color	73.30% <ø> (ø)
ubuntu-latest	73.70% <ø> (ø)

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