feat(tensorflow): support list types inputs

[enmanuelmag]

Fix bug on _postprocess function when the response of model is more than one element

What does this PR address?

Fixes #3806

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[aarnphm]

Would be nice if there is a test case for this. You can write a create a test model under tests/integration/frameworks/models/tensorflow.py

[codecov]

Codecov Report

Merging #3807 (ed9343c) into main (cacc48b) will not change coverage.
The diff coverage is 0.00%.

@@          Coverage Diff          @@
##            main   #3807   +/-   ##
=====================================
  Coverage   0.00%   0.00%           
=====================================
  Files        154     154           
  Lines      12635   12635           
=====================================
  Misses     12635   12635           

Impacted Files	Coverage Δ
src/bentoml/_internal/frameworks/tensorflow_v2.py	0.00% <0.00%> (ø)

[parano]

Thank you for fixing this issue @enmanuelmag!