[docs] Update docs about Cache-Control default headers.

[Gomurmamma]

Closes #33210.

This PR fixes #33210 with an update to the going-to-production.md file about how Cache-Control headers are set by default based on how a page requests data.

Bug

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Feature

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Documentation / Examples

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[balazsorban44]

Thanks. Could we also mention the part how you can override the default in case of gSSP?:

If you want a different Cache-Control while using SSR you can use res.setHeader('Cache-Control', 'value_you_prefer')`

[balazsorban44]

Thanks!

[ijjk]

The stale-while-revalidate header is not set for pages that are automatically statically optimized, only pages that use getStaticProps and return a revalidate value.