Refactor python files in cmd/suggestion

[c-bata]

What this PR does / why we need it:

• Remove __init__.py from cmd/suggestion/**/__init__.py because that are not python import modules, just providing a command-line entrypoint.
• Follow pep8.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):

None.

Special notes for your reviewer:

None.

Release note:

NONE

[kubeflow-bot]

This change is 

[k8s-ci-robot]

Hi @c-bata. 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.

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[c-bata]

/assign @gaocegege

[gaocegege]

/ok-to-test

[c-bata]

/retest

[johnugeorge]

/retest

[c-bata]

/retest

[johnugeorge]

Thanks @c-bata
/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: johnugeorge

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