Pass the pipeline identifier as part of the data prepper config.

[sb2k16]

Description

This PR is to add a pipeline_identifier to the data prepper config to ensure that the multiple pipelines can subscribe to the same KDS stream when using enhanced fan-out strategy. This is optional and by default would use the pipeline name as the identifier for the active subscription.

Issues Resolved

Resolves #1082

Check List

• New functionality includes testing.
• Commits are signed with a real name per the DCO

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