fix(sdk): fixes module not found error for containerized python components. Fixes #8385

[Mithil467]

Description of your changes:
Prepends the module_directory to sys.path. module_directory is WindowsPath object on windows, hence casting to string as sys.path doesn't support pathlib objects.

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[google-oss-prow]

Hi @Mithil467. Thanks for your PR.

I'm waiting for a kubeflow member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[connor-mccarthy]

Thanks, @Mithil467. This is great.

Could you sign the CLA?

Could you also add at least one representative test case for this specific bug to this test file? https://github.com/kubeflow/pipelines/blob/master/sdk/python/kfp/cli/component_test.py

[connor-mccarthy]

Fixes #8385

[Mithil467]

@connor-mccarthy I have signed the CLA.
I have also added a new unit test, let me know if this is good enough.

[connor-mccarthy]

/ok-to-test

[connor-mccarthy]

Thanks, @Mithil467. This looks and works great.

You can ignore the kubeflow-pipelines-sdk-execution-tests failures. They are unrelated to your changes.

One request before we merge: could you add a release note about this fix to the "Current Version: Bug fixes and other changes" of sdk/RELEASE.md?

[Mithil467]

Sounds good, thanks @connor-mccarthy

[google-oss-prow]

@Mithil467: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
kubeflow-pipelines-sdk-execution-tests	27a9ce9	link	true	/test kubeflow-pipelines-sdk-execution-tests

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. I understand the commands that are listed here.

[connor-mccarthy]

/lgtm
/approve

Thank you for this, @Mithil467! The community will benefit greatly from this fix.

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: connor-mccarthy

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