Update 4.0

[nfahlgren]

Describe your changes
Merges updates from main and 4.x into the release-4.0 branch.

Type of update
Is this a: Update

For the reviewer
See this page for instructions on how to review the pull request.

• PR functionality reviewed in a Jupyter Notebook
• All tests pass
• Test coverage remains 100%
• Documentation tested
• New documentation pages added to plantcv/mkdocs.yml
• Changes to function input/output signatures added to updating.md
• Code reviewed
• PR approved

[codecov]

Codecov Report

Merging #944 (4390066) into release-4.0 (696704c) will not change coverage.
The diff coverage is 100.00%.

@@              Coverage Diff              @@
##           release-4.0      #944   +/-   ##
=============================================
  Coverage       100.00%   100.00%           
=============================================
  Files              160       161    +1     
  Lines             6827      6840   +13     
=============================================
+ Hits              6827      6840   +13     

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/_helpers.py	100.00% <100.00%> (ø)
plantcv/plantcv/analyze_bound_horizontal.py	100.00% <100.00%> (ø)
plantcv/plantcv/analyze_bound_vertical.py	100.00% <100.00%> (ø)
plantcv/plantcv/analyze_object.py	100.00% <100.00%> (ø)
plantcv/plantcv/crop_position_mask.py	100.00% <100.00%> (ø)
plantcv/plantcv/find_objects.py	100.00% <100.00%> (ø)
plantcv/plantcv/morphology/_iterative_prune.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)
... and 11 more