Fix client side Validation Error on imported schemas with invalid field names

Reproduction steps :

• Create a new schema using "Import" in advanced settings
• Select an xsd file containing an invalid field name (i.e finishing by "Type")
• Once created without error server side, the schema page is displayed correctly
• When you try to save, a Validation Error alert pops up saying there is an invalid name for a field because the suffix 'Type' is reserved.

As the validation passed server side and the schema is readonly, it should not be validated on client side