fix unused value error

Author: mununki

cli/reactjs_jsx_ppx.ml

@@ -1592,7 +1592,7 @@ module V4 = struct
                 For example, if JSX ppx is used for React Native, type would be different.
              *)
              match interiorType with
-             | {ptyp_desc = Ptyp_var label} -> Some (refType Location.none)
+             | {ptyp_desc = Ptyp_var "ref"} -> Some (refType Location.none)
              | _ ->
                (* Strip explicit Js.Nullable.t in case of forwardRef *)
                if stripExplicitJsNullableOfRef then stripJsNullable interiorType