Update src/CacheTower.Extensions.Redis/RedisLockExtension.cs

Co-authored-by: James Turner <Turnerj@users.noreply.github.com>

Author: mgoodfellow

src/CacheTower.Extensions.Redis/RedisLockExtension.cs

@@ -92,7 +92,7 @@ public async ValueTask<CacheEntry<T>> WithRefreshAsync<T>(string cacheKey, Func<
 				{
 					var tcs = new TaskCompletionSource<bool>();
 					var cts = new CancellationTokenSource(Options.LockTimeout);
-					cts.Token.Register(() => tcs.TrySetCanceled(), useSynchronizationContext: false);
+					cts.Token.Register(tcs => ((TaskCompletionSource<bool>)tcs).TrySetCanceled(), tcs, useSynchronizationContext: false);
 					return tcs;
 				});