Fix object detection / keypoint detection / instance segmentation

[ethanwharris]

What does this PR do?

Makes the following changes:

• fixes the examples
• adds the examples to the ci
• fixes a bug where transforms where not being called

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• Did you make sure to update the documentation with your changes?
• Did you write any new necessary tests? [not needed for typos/docs]
• Did you verify new and existing tests pass locally with your changes?
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[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@924aee8). Click here to learn what that means.
The diff coverage is 100.00%.

❗ Current head 791db69 differs from pull request most recent head 8b8b0b0. Consider uploading reports for the commit 8b8b0b0 to get more accurate results

@@            Coverage Diff            @@
##             master    #1072   +/-   ##
=========================================
  Coverage          ?   87.61%           
=========================================
  Files             ?      281           
  Lines             ?    12790           
  Branches          ?        0           
=========================================
  Hits              ?    11206           
  Misses            ?     1584           
  Partials          ?        0           

Flag	Coverage Δ
unittests	87.61% <100.00%> (?)

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

Impacted Files	Coverage Δ
flash/core/data/data_module.py	94.89% <100.00%> (ø)
flash/core/data/io/input_transform.py	73.86% <100.00%> (ø)
flash/image/detection/data.py	94.23% <100.00%> (ø)
flash/image/instance_segmentation/data.py	95.45% <100.00%> (ø)
flash/image/keypoint_detection/data.py	94.28% <100.00%> (ø)
flash/image/keypoint_detection/input_transform.py	100.00% <100.00%> (ø)

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