Update error message for TypeTransformerFailedError

[wayner0628]

Tracking issue

Related to flyteorg/flyte#5353

Why are the changes needed?

1. To raise TypeTransformerFailedError directly and provide clearer feedback on unsupported type transformations instead of internal AttributeError messages like AttributeError: 'NoneType' object has no attribute 'string_value'.
2. To validate the literal for each registered SimpleTransformer, ensuring more robust type handling.

What changes were proposed in this pull request?

1. Remove the try-except code block that raises an AttributeError when a SimpleTransformer receives an incorrect literal format.
2. Add individual checks for each SimpleTransformer currently supported by flytekit.

How was this patch tested?

Executed unit tests using:

pytest /flytekit/tests/flytekit/unit/core/test_type_engine.py

Screenshots

Running the above unit test on the master branch:

Running the above unit test on this new branch: fix-check-simpletransformer-get-union-type-error

-> No additional errors occur.

Check all the applicable boxes

• I updated the documentation accordingly.
• All new and existing tests passed.
• All commits are signed-off.

Related PRs

N/A

Docs link

N/A

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[wayner0628]

Fixed the check fail where None types were handled improperly in the program.

[codecov]

Codecov Report

Attention: Patch coverage is 9.09091% with 20 lines in your changes missing coverage. Please review.

Project coverage is 54.83%. Comparing base (72da0d0) to head (6460cf7).
Report is 1 commits behind head on master.

Files	Patch %	Lines
flytekit/core/type_engine.py	9.09%	10 Missing and 10 partials ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #2648       +/-   ##
===========================================
- Coverage   78.77%   54.83%   -23.94%     
===========================================
  Files         187      236       +49     
  Lines       19149    21554     +2405     
  Branches     3993     3781      -212     
===========================================
- Hits        15085    11820     -3265     
- Misses       3374     9224     +5850     
+ Partials      690      510      -180     

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