Update WixSharp 2.7.3

Author: christophwille

ILSpy.Installer/ILSpy.Installer.csproj

@@ -23,7 +23,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixSharp_wix4" Version="2.6.1" />
+    <PackageReference Include="WixSharp_wix4" Version="2.7.3" />
   </ItemGroup>
 
   <Target Name="PostBuild" AfterTargets="PostBuildEvent">