Remove duplication, improve readability, and expand tests for
`TestWebhooks.ts` - in anticipation for storing test webhooks in Redis.
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Co-authored-by: कारतोफ्फेलस्क्रिप्ट™ <aditya@netroy.in>
Ensure all errors in `cli` inherit from `ApplicationError` to continue
normalizing all the errors we report to Sentry
Follow-up to: https://github.com/n8n-io/n8n/pull/7820