Test that KafkaSource KEDA annotations are correctly applied

[Cali0707]

Problem
We support configuring scaling of KafkaSources through annotations. We should have an e2e test checking that these are correctly applied.

Persona:
Which persona is this feature for?

Exit Criteria
An e2e test indicating that these parameters are correctly applied

Time Estimate (optional):
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Additional context (optional)
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[Cali0707]

/help

[knative-prow]

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