Serve sanity checks

[ethanwharris]

What does this PR do?

Fixes # (issue)

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[codecov]

Codecov Report

Merging #423 (7aa3835) into master (089c4e8) will increase coverage by 1.34%.
The diff coverage is 94.96%.

@@            Coverage Diff             @@
##           master     #423      +/-   ##
==========================================
+ Coverage   89.97%   91.31%   +1.34%     
==========================================
  Files         112      112              
  Lines        7003     7060      +57     
==========================================
+ Hits         6301     6447     +146     
+ Misses        702      613      -89     

Flag	Coverage Δ
unittests	91.31% <94.96%> (+1.34%)	⬆️

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

Impacted Files	Coverage Δ
flash/core/utilities/imports.py	90.90% <ø> (ø)
flash/core/data/data_pipeline.py	94.37% <66.66%> (+0.39%)	⬆️
flash/core/trainer.py	87.20% <85.71%> (-0.45%)	⬇️
flash/core/model.py	84.80% <88.23%> (+6.49%)	⬆️
flash/core/serve/flash_components.py	88.52% <96.29%> (+38.52%)	⬆️
flash/__init__.py	89.47% <100.00%> (+0.58%)	⬆️
flash/core/classification.py	96.47% <100.00%> (+2.81%)	⬆️
flash/core/data/process.py	85.84% <100.00%> (+0.63%)	⬆️
flash/image/classification/data.py	94.18% <100.00%> (+4.18%)	⬆️
flash/image/classification/model.py	86.36% <100.00%> (ø)
... and 13 more

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[Borda]

shall t be rather just 0/1?

[ethanwharris]

Not sure if it can be. This was done by the fiftyone people for something on their end. I wouldn't want to change it in case something breaks.

[Borda]

yep, some variables are 0/1 other you write s true... lets be consistent

[tchaton]

Looks great ! Know we can add an extra sanity call to the Trainer.

[tchaton]

LGTM !