Update Reference to reflect value described for processBeforeResponse

[harunsmrkovic]

Summary

Reference Docs explain what is processBeforeResponse, but then say that value used to accomplish this is false. However, if you want to ensure that "event listeners don't unexpectedly terminate", you must set this value to true.

This is also visible in the AWS Lambda docs: https://slack.dev/bolt-js/deployments/aws-lambda#prepare-the-app

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[CLAassistant]

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[seratch]

Hi @harunsmrkovic, thanks for pointing this out. You are right. The document had been incorrect 🙇