Fixed nil panic scenarios.

[bendory]

Changes

Prior to this change, some test failures resulted in nil panic. With this change, said failures will instead provide helpful error messages.

Submitter Checklist

As the author of this PR, please check off the items in this checklist:

• [N/A] Has Docs included if any changes are user facing
• [N/A] Has Tests included if any functionality added or changed
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/kind bug

Release Notes

NONE

[bendory]

/assign @lbernick

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dibyom

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[jerop]

/lgtm