Fix showBlobInteractionZones throwing an error when no data exists

What does this MR do?

Fixes an error getting thrown in showBlobInteractionZones when no data exists.

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Does this MR meet the acceptance criteria?

Conformity

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Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
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Security

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