Fixed linter issues; added gci and importas rules.

[carlbraganza]

What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespaces from that line:

/kind api-change
/kind bug
/kind cleanup
/kind design
/kind documentation
/kind failing-test
/kind feature
/kind flake

What this PR does / why we need it:
Cleans up linter errors.

Which issue(s) this PR fixes:

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[carlbraganza]

/assign @PrasadG193
/assign @pavannd1

[k8s-ci-robot]

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In response to this:

/assign @PrasadG193
/assign @pavannd1

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[PrasadG193]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: carlbraganza, PrasadG193

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