fix: Prevent demo data from being created on edited tables

[vsgoulart]

With the table component we added the concept of adding demo data to the new component, this data was being added when importing forms into the modeler.
This PR prevents this from happening and only adds the demo data when the schema matches with the demo data

Closes #997

• This PR adds a new form-js element or visually changes an existing component.
  • => In that case, we need to ensure we follow up on this, e.g. by creating an issue in Tasklist

[Skaiir]

Generally, let's be careful with these kinds of changes. Our config object is tied in with the custom component framework and should be treated more or less as public API. Of course we're never obligated but changing how it's structured is something we should not do often.

I highly doubt anyone was using this already, considering how unique this stuff is, but this a breaking change if we were very strict about it.

Maybe it's worth annotating this as experimental, so that we can be safe in the future if we do decide to remove it entirely (which I believe will happen when we have more robust ways of doing demo data).

[Skaiir]

Or moving it to an experimental sub-object, which should get the point across 🤔

[vsgoulart]

@Skaiir I added the @experimental tag