Add new channels configs

[matzew]

Fixes #512

Proposed Changes

• adding kafka channels (CRD / CCP) to release script (Kafka Channel was not released in 0.8.0 #512)
• adding natss channel (CRD) to release script (was not added with Add Nats channel CRD implementation #491)

Release Note

Fixes issue from 0.8.0 to include the missing kafka channels on eventing-contrib release

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[matzew]

@grantr besides the missing kafka, I also added the natss channel CRD (since touching the file), since the PR for adding it was also not updating the release script