admin_showroom can only edit sample of his own showroom

config/sync/field.storage.node.field_samples.yml

@@ -3,8 +3,12 @@ langcode: en
 status: true
 dependencies:
   module:
+    - field_permissions
     - materio_samples
     - node
+third_party_settings:
+  field_permissions:
+    permission_type: custom
 id: node.field_samples
 field_name: field_samples
 entity_type: node
@@ -12,7 +16,7 @@ type: materio_samples_field
 settings: {  }
 module: materio_samples
 locked: false
-cardinality: -1
+cardinality: 4
 translatable: true
 indexes: {  }
 persist_with_no_fields: false