Rebase from master

[HaleySchuhl]

Describe your changes
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What was the previous functionality (if relevant) and what can we do now with
these changes.

Type of update
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• Bug fix
• New feature or feature enhancement
• Update to documentation
• Work in progress

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[codecov]

Codecov Report

Merging #854 (5758875) into 4.x (a086228) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##               4.x      #854    +/-   ##
==========================================
  Coverage   100.00%   100.00%            
==========================================
  Files          151       151            
  Lines         6679      6527   -152     
==========================================
- Hits          6679      6527   -152     

Flag	Coverage Δ
unittests	100.00% <100.00%> (ø)

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

Impacted Files	Coverage Δ
plantcv/plantcv/cluster_contour_mask.py	100.00% <ø> (ø)
plantcv/plantcv/spectral_index/spectral_index.py	100.00% <ø> (ø)
plantcv/plantcv/threshold/threshold_methods.py	100.00% <ø> (ø)
...lantcv/plantcv/hyperspectral/extract_wavelength.py	100.00% <100.00%> (ø)
plantcv/plantcv/morphology/analyze_stem.py	100.00% <100.00%> (ø)
plantcv/plantcv/morphology/check_cycles.py	100.00% <100.00%> (ø)
plantcv/plantcv/morphology/find_branch_pts.py	100.00% <100.00%> (ø)
plantcv/plantcv/morphology/find_tips.py	100.00% <100.00%> (ø)
plantcv/plantcv/morphology/prune.py	100.00% <100.00%> (ø)
plantcv/plantcv/morphology/segment_angle.py	100.00% <100.00%> (ø)
... and 18 more