bug(opm): packages flag on registry rm required

[djzager]

Description of the change:

The packages flag on opm registry rm is necessary in order for work to
be done. This update marks the flag as required so the usage can be
printed when the flag is ommitted.

Motivation for the change:

💥🐛

Reviewer Checklist

• Implementation matches the proposed design, or proposal is updated to match implementation
• Sufficient unit test coverage
• Sufficient end-to-end test coverage
• Docs updated or added to /docs
• Commit messages sensible and descriptive

Closes #250

[openshift-ci-robot]

Hi @djzager. Thanks for your PR.

I'm waiting for a operator-framework 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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[kevinrizza]

/ok-to-test
/approve

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: djzager, kevinrizza

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[ecordell]

/lgtm