Add newline at end of demo_schema.gql

Author: dconeybe

firebase-dataconnect/emulator/dataconnect/schema/demo_schema.gql

@@ -341,4 +341,4 @@ type AnyScalarNonNullableListOfNonNullable @table @index(fields: ["tag"]) {
 type OrderDirectionTest @table @index(fields: ["tag"]) {
   value: Int
   tag: String
-}
+}