Update mstest to get correct parallel output (#3535)

Author: nohwnd

scripts/build/TestPlatform.Dependencies.props

@@ -15,8 +15,8 @@
 
     <!-- These versions are used for running unit tests, and running acceptance tests. They are also used as the default version for projects
     in TestAssets.sln to allow running and debugging tests in that solution directly in VS without having to run them via AcceptanceTests. -->
-    <MSTestFrameworkVersion>2.2.8</MSTestFrameworkVersion>
-    <MSTestAdapterVersion>2.2.8</MSTestAdapterVersion>
+    <MSTestFrameworkVersion>2.2.9-preview-20220210-07</MSTestFrameworkVersion>
+    <MSTestAdapterVersion>2.2.9-preview-20220210-07</MSTestAdapterVersion>
     <MSTestAssertExtensionVersion>1.0.3-preview</MSTestAssertExtensionVersion>