source property of CubeMapTexture could be confusing

source property of CubeMapTexture can accept 6 images. But when there are new lines between each image path, the app doesn't work as expected.

https://git.qt.io/se_japan_public/automotive-related/outrun_xr/-/blob/QtLeadersSummit2024Japan/Main.qml?ref_type=heads#L66

But when they are all written in one line, it does.

https://git.qt.io/se_japan_public/automotive-related/outrun_xr/-/commit/163a7894a96a2958bffdd16ca4926132647e2039

A few improvement ideas:

1. accept list instead of a series of strings
2. the documentation to have a warning about new line