[cpack_installer] added option to override the inclusion of test targets in build

cmake/PAL.cmake

@@ -85,3 +85,9 @@ ly_include_cmake_file_list(${pal_dir}/platform_${PAL_PLATFORM_NAME_LOWERCASE}_fi
 
 include(${pal_dir}/PAL_${PAL_PLATFORM_NAME_LOWERCASE}.cmake)
 include(${pal_dir}/Toolchain_${PAL_PLATFORM_NAME_LOWERCASE}.cmake OPTIONAL)
+
+set(LY_DISABLE_TEST_MODULES FALSE CACHE BOOL "Option to forcibly disable the inclusion of test targets in the build")
+
+if(LY_DISABLE_TEST_MODULES)
+    ly_set(PAL_TRAIT_BUILD_TESTS_SUPPORTED FALSE)
+endif()