Update string_test.ri

Author: StunxFS

lib/core/tests/string_test.ri

@@ -13,7 +13,7 @@ test "string.fmt()" {
         "reverse order: {2}, {1}, {0}".fmt(1, 2, 3) == "reverse order: 3, 2, 1"
     );
 
-    // FIXME: fix len 10 != 9 -> @assert("rune: `{}`".fmt('Á') == "rune: `Á`");
+    @assert("rune: `{}`".fmt('Á') == "rune: `Á`");
 
     @assert("{0:-4}k".fmt(1) == "1   k");
     @assert("{:4}k".fmt(2004) == "2004k");