Return from RunWithCancel if cmd is kapp

[devanshuVmware]

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #1627

Does this PR introduce a user-facing change?

NONE

Additional Notes for your reviewer:

Review Checklist:

• Follows the developer guidelines
• Relevant tests are added or updated
• Relevant docs in this repo added or updated
• Relevant carvel.dev docs added or updated in a separate PR and there's
  a link to that PR
• Code is at least as readable and maintainable as it was before this
  change

Additional documentation e.g., Proposal, usage docs, etc.:

[rohitagg2020]

I am thinking if we should add a test case or not (As it has been reported by 2 different users)? We can mock the data in the path /var/run/secrets/kubernetes.io and try to run kctrl pkg release command and ensure that it completes successfully.