feat(attributes): dynamic default (#3379)

Author: mylesj

Diff for: packages/core/src/helpers/getAttributesFromExtensions.ts

@@ -93,7 +93,11 @@ export function getAttributesFromExtensions(extensions: Extensions): ExtensionAt
           ...attribute,
         }
 
-        if (attribute?.isRequired && attribute?.default === undefined) {
+        if(typeof mergedAttr?.default === 'function') {
+          mergedAttr.default = mergedAttr.default()
+        }
+
+        if (mergedAttr?.isRequired && mergedAttr?.default === undefined) {
           delete mergedAttr.default
         }