[cherry-pick 0.10.x] Ensure taskRef is non nil before setting defaults as this is an optio…

[vdemeester]

Changes

Cherry pick of #1966

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[piyush-garg]

/lgtm

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[bobcatfish]

Sine this was a cherry pick, no real CLA issue here!

[takirala]

@abayer @imjasonh could you please review ?

[takirala]

@googlebot I consent

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: piyush-garg, sbwsg

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