Add create requestOpts method to {{classname}}Interface #21708

[azertyalex]

This PR splits some logic, instead of creating/building the request inline and sending it instantly we now use a function to do this. Functionally there should be no changes.

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[btpnlsl]

The interface in Runtime.ts is RequestOpts. It might be better to refer to this as {{nickname}}RequestOpts instead of {{nickname}}RequestConfig & creates request options as otherwise the name of the method may be misleading.

[azertyalex]

In some libraries it's called request config, such as axios. But it indeed makes more sense to have opts/options here.

[btpnlsl]

You should be able to return the object directly without having a intermediate variable.

[azertyalex]

you're right. writing code in mustache is hard

[azertyalex]

fix #21708