fixed failed compilation due to missing getStdErr from std.io

[abhijitmamarde]

fixed for issue:

move.zig:14:26: error: root source file struct 'Io' has no member named 'getStdErr'
    const stderr = std.io.getStdErr().writer();
                   ~~~~~~^~~~~~~~~~
/opt/homebrew/Cellar/zig/0.15.2/lib/zig/std/Io.zig:1:1: note: struct declared here
const builtin = @import("builtin");
^~~~~