Parallelize efficiency script

[mcoughlin]

Efficiency estimation is too slow. Should be improved...

[codecov]

Codecov Report

Merging #70 (9ba40f9) into main (ceeb79c) will decrease coverage by 0.18%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main      #70      +/-   ##
==========================================
- Coverage   30.54%   30.36%   -0.19%     
==========================================
  Files          35       35              
  Lines        1673     1683      +10     
==========================================
  Hits          511      511              
- Misses       1162     1172      +10     

Impacted Files	Coverage Δ
dorado/scheduling/scripts/survey_slicer.py	5.47% <0.00%> (-0.41%)	⬇️

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[mcoughlin]

Unit tests pass. Merging.