chore: import upstream snapshot with attribution

dotnet/tests/AgentConformance.IntegrationTests/AgentTests.cs

@@ -0,0 +1,29 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Threading.Tasks;
+
+namespace AgentConformance.IntegrationTests;
+
+/// <summary>
+/// Base class for all test classes used for testing agents.
+/// </summary>
+/// <typeparam name="TAgentFixture">The type of the agent fixture used in these tests.</typeparam>
+/// <param name="createAgentFixture">Used to create a new fixture for this test suite.</param>
+public abstract class AgentTests<TAgentFixture>(Func<TAgentFixture> createAgentFixture) : IAsyncLifetime
+    where TAgentFixture : IAgentFixture
+{
+    protected TAgentFixture Fixture { get; private set; } = default!;
+
+    public async ValueTask InitializeAsync()
+    {
+        this.Fixture = createAgentFixture();
+        await this.Fixture.InitializeAsync();
+    }
+
+    public async ValueTask DisposeAsync()
+    {
+        GC.SuppressFinalize(this);
+        await this.Fixture.DisposeAsync();
+    }
+}