fix(form): prevent reload loop with rjsf v5.20

[miguelgrc]

Closes #72

rjsf 5.20 was causing issues with our e2e tests since sometimes, when dragging new (e.g. select) fields to the tree some of them would be typed as text fields. This is related to our use of rawErrors in the our custom validation function to pass down the path to FieldTemplate.

It turns out the error was being caused by this change in rjsf. That mergeObjects there with the preventDuplicates argument returns a deep copy of the object when called with two equal objects, meaning that the errorSchema object returned is essentially a new one. properties.content.props in ObjectFieldTemplate contains errorSchema, therefore it reloads when the errorSchema changes (after that change in rjsf it now does so on every validation call), causing cards to change, causing the uiSchema to be updated in the store, causing the Form in SchemaTree to refresh (as uiSchema is an object and useSelector uses a shallow equality check*), triggering a new validation, and continuing the endless loop.

The solution has been to add an extra check in ObjectFieldTemplate so that changes in cards only dispatch an update to the uiSchema when the order of the cards changes, and not in every situation when the cards array changes (which in fact happens on every re-render as it's an array and arrays are compared by reference, returning false even if both arrays have the same content, which is generally the case here). This breaks that loop.

Note: The way we use rawErrors to pass the path to the FieldTemplate is a bit hackish, but seeing that it keeps working after this change I would maintain it for the time being. There is no rjsf way of getting the path information functions such as toPathSchema only return the "path" from the current element to its children, but not from the root to the current element, which is what we need. So, the alternative, if we end up wanting to change this, could be to have a paths object in the redux store and populate it in the addByPath action, and we also would have to populate it on startup when loading an existing schema by traversing it completely. We would also have to disallow duplicate field ids everywhere in the form.

*We should consider using Immer for the Redux state to better protect ourselves against these situations

[pamfilos]

Merged with #77