Add "macOS shuffle" to iOS as well

Since iOS functions like macOS with regards to Alt behaving like AltGr,
we need the same workaround on iOS as well.

core/input/keyboard.js

@@ -135,7 +135,7 @@ export default class Keyboard {
         // keys around a bit to make things more sane for the remote
         // server. This method is used by RealVNC and TigerVNC (and
         // possibly others).
-        if (browser.isMac()) {
+        if (browser.isMac() || browser.isIOS()) {
             switch (keysym) {
                 case KeyTable.XK_Super_L:
                     keysym = KeyTable.XK_Alt_L;