conanfile should be visible in project tree when it's used

Qt Creator has conan package manager integration that automatically uses conanfile.txt / conanfile.py. It should be possible to add the conanfile into CMAKE_CONFIGURE_DEPENDS property, so that it's visible in the project tree, and CMake is reconfigured automatically on conanfile changes. The upstream cmake-conan already does this today: conan_provider.cmake#L497

This can be replicated by using the following CMake command:

set_property(
  DIRECTORY ${CMAKE_SOURCE_DIR}
  APPEND
  PROPERTY CMAKE_CONFIGURE_DEPENDS "${CMAKE_SOURCE_DIR}/conanfile.py")