Updated build version requirement to 0.10.0-dev.3385

exercises/050_no_value.zig

@@ -71,6 +71,7 @@ pub fn main() void {
     var first_line2: Err!*const [21]u8 = ???;
     first_line2 = "which can eternal lie";
 
+    // Note we need the "{!s}" format for the error union string.
     std.debug.print("{s} {!s} / ", .{ first_line1, first_line2 });
 
     printSecondLine();