fix(#85) use of reuse_port deprecated (#86)

src/04-01.zig

@@ -15,7 +15,7 @@ pub fn main() !void {
     const loopback = try net.Ip4Address.parse("127.0.0.1", 0);
     const localhost = net.Address{ .in = loopback };
     var server = try localhost.listen(.{
-        .reuse_port = true,
+        .reuse_address = true,
     });
     defer server.deinit();