Remove "cancel countdown" tooltip on multiplayer ready button (#37143)

- Closes https://github.com/ppy/osu/issues/37142

Not relevant anymore after
https://github.com/ppy/osu/commit/9963efce517068bbb7232374097ac88e8be1979d.

osu.Game/Screens/OnlinePlay/Multiplayer/Match/MultiplayerReadyButton.cs

@@ -8,7 +8,6 @@ using osu.Framework.Allocation;
 using osu.Framework.Audio;
 using osu.Framework.Audio.Sample;
 using osu.Framework.Extensions.ObjectExtensions;
-using osu.Framework.Localisation;
 using osu.Framework.Threading;
 using osu.Game.Graphics;
 using osu.Game.Online.Multiplayer;
@@ -227,21 +226,5 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
             if (multiplayerClient.IsNotNull())
                 multiplayerClient.RoomUpdated -= onRoomUpdated;
         }
-
-        public override LocalisableString TooltipText
-        {
-            get
-            {
-                if (room?.ActiveCountdowns.Any(c => c is MatchStartCountdown) == true
-                    && multiplayerClient.IsHost
-                    && multiplayerClient.LocalUser?.State == MultiplayerUserState.Ready
-                    && !room.Settings.AutoStartEnabled)
-                {
-                    return "Cancel countdown";
-                }
-
-                return base.TooltipText;
-            }
-        }
     }
 }