Inform developers of defaults YAML option

[1000TurquoisePogs]

This is a small update to suggest a pattern I've seen extenders do that has been useful to them.
By shipping their own defaults YAML file, and telling users to append it to the overall config, they can reduce user actions upon installing an extension.

files changed
docs/extend/packaging-zos-extensions.md

[github-actions]

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[github-actions]

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[Martin-Zeithaml]

https://github.com/zowe/api-layer/blob/v3.x.x/api-catalog-package/src/main/resources/manifest.yaml