WIP: test: Re-enable KFP Dockerfile-CLI component SDK unit test

[DharmitD]

Removed the skip unit test decorator that was previously added to bypass the test due to failure (referencing issue #11038).

The issue reported in #11038 was caused due to the Dockerfile referencing to Python 3.7. With the Python version updated to 3.9 (done as part of this commit), the test now passes consistently. This commit re-enables the test to ensure proper validation of Dockerfile creation and KFP package.

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