Upgrade cppwinrt solution to Visual Studio 2022 (#1187)

Author: kennykerr

Directory.Build.Props

@@ -3,9 +3,7 @@
   <!-- Set common MSBuild properties and item metadata for CppWinRT tool and tests -->
 
   <PropertyGroup>
-    <PlatformToolset Condition="'$(PlatformToolset)'=='' and '$(VisualStudioVersion)' == '15.0'">v141</PlatformToolset>
-    <PlatformToolset Condition="'$(PlatformToolset)'=='' and '$(VisualStudioVersion)' == '16.0'">v142</PlatformToolset>
-    <PlatformToolset Condition="'$(PlatformToolset)'==''">v143</PlatformToolset>
+    <PlatformToolset>v143</PlatformToolset>
     <WindowsTargetPlatformVersion>10.0</WindowsTargetPlatformVersion>
     <WindowsTargetPlatformMinVersion>10.0.18362.0</WindowsTargetPlatformMinVersion>
   </PropertyGroup>
@@ -46,7 +44,7 @@
       <SDLCheck>true</SDLCheck>
       <ConformanceMode>true</ConformanceMode>
       <LanguageStandard Condition="'$(CppWinRTLanguageStandard)'==''">stdcpp17</LanguageStandard>
-      <LanguageStandard Condition="'$(CppWinRTLanguageStandard)'=='latest'">stdcpplatest</LanguageStandard>
+      <LanguageStandard Condition="'$(CppWinRTLanguageStandard)'=='20'">stdcpp20</LanguageStandard>
       <PrecompiledHeader>Use</PrecompiledHeader>
       <PrecompiledHeaderFile>pch.h</PrecompiledHeaderFile>
       <PreprocessorDefinitions>CPPWINRT_VERSION_STRING="$(CppWinRTBuildVersion)";%(PreprocessorDefinitions)</PreprocessorDefinitions>