Tests: Prepare RunCMake.CPack_WIX to cover multiple WiX versions

Tests/RunCMake/CPack_WIX/3-AppWiX-cpack-WIX-stdout.txt

@@ -8,4 +8,4 @@ CPack: -   Install component: headers
 CPack: -   Install component: libraries
 CPack: Create package
 CPack: - package: [^
-]*/Tests/RunCMake/CPack_WIX/AppWiX-build/MyLib-1\.0\.0-(win64|windows-arm64)\.msi generated\.
+]*/Tests/RunCMake/CPack_WIX/3-AppWiX-build/MyLib-1\.0\.0-(win64|windows-arm64)\.msi generated\.

Tests/RunCMake/CPack_WIX/RunCMakeTest.cmake

@@ -1,7 +1,16 @@
 include(RunCPack)
 
+set(env_PATH "$ENV{PATH}")
+
 set(RunCPack_GENERATORS WIX)
+set(RunCPack_GLOB *.msi)
+set(RunCPack_VERIFY powershell -ExecutionPolicy Bypass -File ${CMAKE_CURRENT_LIST_DIR}/print-msi.ps1)
 
-set(ENV{PATH} "${CMake_TEST_CPACK_WIX3};$ENV{PATH}")
+function(run_cpack_wix v)
+  run_cpack(${v}-AppWiX SAMPLE AppWiX BUILD)
+endfunction()
 
-run_cpack(AppWiX BUILD GLOB *.msi VERIFY powershell -ExecutionPolicy Bypass -File ${CMAKE_CURRENT_LIST_DIR}/print-msi.ps1)
+if(CMake_TEST_CPACK_WIX3)
+  set(ENV{PATH} "${CMake_TEST_CPACK_WIX3};${env_PATH}")
+  run_cpack_wix(3)
+endif()