Add instance segmentation and keypoint detection to flash zero

[ethanwharris]

What does this PR do?

Fixes # (issue)

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[codecov]

Codecov Report

Merging #672 (438c0b2) into master (741a838) will decrease coverage by 0.34%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #672      +/-   ##
==========================================
- Coverage   89.95%   89.60%   -0.35%     
==========================================
  Files         186      188       +2     
  Lines        9696     9730      +34     
==========================================
- Hits         8722     8719       -3     
- Misses        974     1011      +37     

Flag	Coverage Δ
unittests	89.60% <100.00%> (-0.35%)	⬇️

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

Impacted Files	Coverage Δ
flash/__main__.py	95.23% <ø> (ø)
flash/core/utilities/imports.py	89.28% <100.00%> (+0.09%)	⬆️
flash/image/instance_segmentation/cli.py	100.00% <100.00%> (ø)
flash/image/keypoint_detection/cli.py	100.00% <100.00%> (ø)
flash/graph/classification/model.py	37.70% <0.00%> (-62.30%)	⬇️
flash/graph/data.py	45.00% <0.00%> (-50.00%)	⬇️
flash/graph/classification/cli.py	42.85% <0.00%> (-50.00%)	⬇️
flash/graph/classification/data.py	65.51% <0.00%> (-27.59%)	⬇️
... and 7 more

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[tchaton]

Looks great !