Update dependency WixToolset.Dtf.CustomAction to v6

Author: dependencyupdates[bot]

src/ServicePulse.Install.CustomActions/ServicePulse.Install.CustomActions.csproj

@@ -9,7 +9,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="WixToolset.Dtf.CustomAction" Version="5.0.2" />
+    <PackageReference Include="WixToolset.Dtf.CustomAction" Version="6.0.2" />
   </ItemGroup>
 
    <ItemGroup>