increased timeout + cleanup (#7175)

src/Bicep.LangServer.IntegrationTests/Helpers/MultipleMessageListener.cs

@@ -2,21 +2,24 @@
 // Licensed under the MIT License.
 
 using System.Collections.Generic;
-using System.Diagnostics.CodeAnalysis;
 using System.Threading.Tasks;
 
 namespace Bicep.LangServer.IntegrationTests
 {
-    // helper class to read messages in order and assert things about them
-    [SuppressMessage("Style", "VSTHRD200:Use \"Async\" suffix for async methods", Justification = "Test code does not need to follow this convention.")]
+    /// <summary>
+    /// Helper class to read messages in order and assert things about them.
+    /// </summary>
     public class MultipleMessageListener<T>
     {
-        private object lockObj = new object();
+        private const int DefaultTimeout = 30000;
+
+        private readonly object lockObj = new();
+        private readonly List<TaskCompletionSource<T>> completionSources = new();
+
         private int listenPosition = 0;
-        private int writePosition = 0;
-        private List<TaskCompletionSource<T>> completionSources = new List<TaskCompletionSource<T>>();
+        private int writePosition = 0;        
 
-        public async Task<T> WaitNext(int timeout = 10000)
+        public async Task<T> WaitNext(int timeout = DefaultTimeout)
         {
             Task<T> onMessageTask;
             lock (lockObj)
@@ -33,7 +36,7 @@ public async Task<T> WaitNext(int timeout = 10000)
             return await IntegrationTestHelper.WithTimeoutAsync(onMessageTask, timeout);
         }
 
-        public async Task EnsureNoMessageSent(int timeout = 10000)
+        public async Task EnsureNoMessageSent(int timeout = DefaultTimeout)
         {
             Task<T> onMessageTask;
             lock (lockObj)