Cancel some delay tasks if they're not being used

src/NadekoBot/Modules/Gambling/BlackJack/Blackjack.cs

@@ -97,14 +97,23 @@ public class Blackjack
 
     private async Task PromptUserMove(User usr)
     {
-        var pause = Task.Delay(20000); //10 seconds to decide
+        using var cts = new CancellationTokenSource();
+        var pause = Task.Delay(20000, cts.Token); //10 seconds to decide
         CurrentUser = usr;
         currentUserMove = new();
         await PrintState();
         // either wait for the user to make an action and
         // if he doesn't - stand
         var finished = await Task.WhenAny(pause, currentUserMove.Task);
-        if (finished == pause) await Stand(usr);
+        if (finished == pause)
+        {
+            await Stand(usr);
+        }
+        else
+        {
+            cts.Cancel();
+        }
+        
         CurrentUser = null;
         currentUserMove = null;
     }

src/NadekoBot/Modules/Music/Services/AyuVoiceStateService.cs

@@ -146,7 +146,8 @@ public sealed class AyuVoiceStateService : INService
             await SendJoinVoiceChannelInternalAsync(guildId, channelId);
 
             // create a delay task, how much to wait for gateway response
-            var delayTask = Task.Delay(2500);
+            using var cts = new CancellationTokenSource();
+            var delayTask = Task.Delay(2500, cts.Token);
 
             // either delay or successful voiceStateUpdate
             var maybeUpdateTask = Task.WhenAny(delayTask, voiceStateUpdatedSource.Task);
@@ -156,8 +157,14 @@ public sealed class AyuVoiceStateService : INService
             // wait for both to end (max 1s) and check if either of them is a delay task
             var results = await Task.WhenAll(maybeUpdateTask, maybeServerTask);
             if (results[0] == delayTask || results[1] == delayTask)
+            {
                 // if either is delay, return null - connection unsuccessful
                 return null;
+            }
+            else
+            {
+                cts.Cancel();
+            }
 
             // if both are succesful, that means we can safely get
             // the values from  completion sources