Define an empty GetTargetPathWithTargetPlatformMoniker target

Closes #754

Author: AArnott

src/Nerdbank.GitVersioning.Tasks/build/PrivateP2PCaching.proj

@@ -22,6 +22,9 @@
   <Target Name="SatelliteDllsProjectOutputGroup" />
   <Target Name="BuiltProjectOutputGroupDependencies" />
   <Target Name="DebugSymbolsProjectOutputGroup" />
+  
+  <!-- WinUI3 seems to want this target -->
+  <Target Name="GetTargetPathWithTargetPlatformMoniker" />
 
   <Import Project="$(NBGV_PrivateP2PAuxTargets)" Condition=" '$(NBGV_PrivateP2PAuxTargets)' != '' " />
 </Project>