Added Visual Studio 2019 Test Agent version 16.10.31321.278. (#13932)

* Added Visual Studio 2019 Test Agent version 16.10.31321.278.

* Fixed name for ARP.

manifests/m/Microsoft/VisualStudio/2019/TestAgent/16.10.31321.278/Microsoft.VisualStudio.2019.TestAgent.yaml

@@ -0,0 +1,28 @@
+# yaml-language-server: $schema=https://aka.ms/winget-manifest.singleton.1.0.0.schema.json
+PackageIdentifier: Microsoft.VisualStudio.2019.TestAgent
+PackageVersion: 16.10.31321.278
+PackageName: Visual Studio Test Agent 2019
+Publisher: Microsoft Corporation
+PackageUrl: https://visualstudio.microsoft.com/
+License: Copyright (c) Microsoft Corporation. All rights reserved.
+LicenseUrl: https://visualstudio.microsoft.com/license-terms/
+Moniker: vs2019-testagent
+Tags:
+- C++
+- vs
+- C#
+- testagent
+Installers:
+- Architecture: x64
+  InstallerType: exe
+  InstallerUrl: https://download.visualstudio.microsoft.com/download/pr/cb1d5164-e767-4886-8955-2df3a7c816a8/bbc9acadb3defd264840100d8021272da8ca578f0f42f9ff5e6afb873a769f6e/vs_TestAgent.exe
+  InstallerSha256: BBC9ACADB3DEFD264840100D8021272DA8CA578F0F42F9FF5E6AFB873A769F6E
+  InstallerSwitches:
+    Silent: --quiet
+    SilentWithProgress: --passive
+    Custom: --wait --productId Microsoft.VisualStudio.Product.TestAgent --channelId VisualStudio.16.Release --channelUri https://aka.ms/vs/16/release/channel --add Microsoft.VisualStudio.Workload.Universal
+ShortDescription: Microsoft.VisualStudio.TestAgent
+PackageLocale: en-US
+ManifestType: singleton
+ManifestVersion: 1.0.0
+