Fix test servers staying alive until their test class ends

src/HotChocolate/AspNetCore/test/AspNetCore.Authorization.Opa.Tests/AuthorizationTests.cs

@@ -203,8 +203,10 @@ private TestServer CreateTestServer(
             });
     }
 
-    public async ValueTask DisposeAsync()
+    public override async ValueTask DisposeAsync()
     {
+        await base.DisposeAsync();
+
         if (_opaHandle is not null)
         {
             await _opaHandle.DisposeAsync();

src/HotChocolate/AspNetCore/test/AspNetCore.Tests.Utilities/ServerTestBase.cs

@@ -12,7 +12,9 @@
 
 namespace HotChocolate.AspNetCore.Tests.Utilities;
 
-public abstract class ServerTestBase(TestServerFactory serverFactory) : IClassFixture<TestServerFactory>
+public abstract class ServerTestBase(TestServerFactory serverFactory)
+    : IClassFixture<TestServerFactory>
+    , IAsyncDisposable
 {
     protected TestServerFactory ServerFactory { get; } = serverFactory;
 
@@ -164,6 +166,16 @@ protected virtual TestServer CreateServer(
                 .UseEndpoints(endpoints => configureConventions?.Invoke(endpoints)));
     }
 
+    /// <summary>
+    /// Disposes the servers the current test created.
+    /// </summary>
+    public virtual ValueTask DisposeAsync()
+    {
+        ServerFactory.DisposeServers();
+
+        return ValueTask.CompletedTask;
+    }
+
     [DirectiveType(DirectiveLocation.Subscription)]
     public class Foo
     {

src/HotChocolate/AspNetCore/test/AspNetCore.Tests.Utilities/TestServerFactory.cs

@@ -13,7 +13,7 @@
         Action<IServiceCollection> configureServices,
         Action<IApplicationBuilder> configureApplication)
     {
         var builder = new WebHostBuilder()
             .Configure(configureApplication)
             .ConfigureServices(services =>
             {
@@ -21,16 +21,23 @@
                 configureServices(services);
             });
 
         var server = new TestServer(builder);
         _instances.Add(server);
         return server;
     }
 
-    public void Dispose()
+    public void Dispose() => DisposeServers();
+
+    /// <summary>
+    /// Disposes and releases every server this factory has created so far.
+    /// </summary>
+    public void DisposeServers()
     {
         foreach (var testServer in _instances)
         {
             testServer.Dispose();
         }
+
+        _instances.Clear();
     }
 }