Update tagging controller's alias

[chewong]

https://github.com/kubernetes/cloud-provider-aws/pull/641 introduced a bug where the controller alias map has the wrong value for the tagging controller:

"tagging" is not in the list of known controllers
Error: "tagging" is not in the list of known controllers

This PR will fix the issue. I have tested it in my cluster and it was able to start the cloud controller manager successfully.

What type of PR is this?

Uncomment only one, leave it on its own 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:

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[k8s-ci-robot]

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[wongma7]

/lgtm /approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: wongma7

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