[Do Not Merge] Temporarily adding logic to create sagemaker client with endpoint url

[leleamol]

Description of changes:

Style and formatting:

I have run pre-commit install to ensure that auto-formatting happens with every commit.

Issue number, if available

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[codecov-io]

Codecov Report

Merging #389 into master will decrease coverage by 20.76%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           master     #389       +/-   ##
===========================================
- Coverage   85.49%   64.72%   -20.77%     
===========================================
  Files          86       86               
  Lines        6514     6517        +3     
===========================================
- Hits         5569     4218     -1351     
- Misses        945     2299     +1354     

Impacted Files	Coverage Δ
smdebug/rules/action/stop_training_action.py	78.46% <100.00%> (+1.04%)	⬆️
smdebug/tensorflow/singleton_utils.py	0.00% <0.00%> (-100.00%)	⬇️
smdebug/tensorflow/collection.py	0.00% <0.00%> (-95.88%)	⬇️
smdebug/tensorflow/keras.py	0.00% <0.00%> (-92.33%)	⬇️
smdebug/tensorflow/tensor_ref.py	0.00% <0.00%> (-88.71%)	⬇️
smdebug/tensorflow/utils.py	0.00% <0.00%> (-88.33%)	⬇️
smdebug/tensorflow/session.py	6.25% <0.00%> (-85.58%)	⬇️
smdebug/tensorflow/base_hook.py	2.38% <0.00%> (-78.18%)	⬇️
smdebug/tensorflow/version_check.py	0.00% <0.00%> (-75.00%)	⬇️
smdebug/tensorflow/__init__.py	37.50% <0.00%> (-62.50%)	⬇️
... and 19 more

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[NihalHarish]

How is this logic being tested?

[leleamol]

How is this logic being tested?

This change we may not want to merge. It made to enable the spot training testing.