Update lights and shadows page for Godot 4.0 (Need help)

[skyace65]

Updates the lights and shadows page for Godot 4.0 Thankfully not too many changes had to be made. Though in the future this page should be expanded with more image examples of settings where necessary.

Also I'm unable to find information on the fog fade and transmittance bias shadow parameters. I tried searching for them in the godot repository and discord and found nothing, and currently the master branch is crashing on me when I add a cube so I can't test. Information on those is the only thing I need to finish this PR.

-Changes the page title to 3D light nodes since the page only goes over the nodes not lights in general.
-Alters the introduction, references to other things such as environment nodes and emissive material felt out of place for a page that's just about light nodes.
-Updates the list of light and shadow parameters.
-Updates the light parameters image, image has gone through png compression.
-Remove the shadow contact image and info, the setting has been removed.
-Changes how page sections are listed.
-Changes references to project settings to use the current format.
-Removed section at the end about soft shadows. The settings are named differently now, and that information makes more sense after the shadow properties.
-Adds a reference to soft shadow project settings under shadow settings.

[mhilbrunner]

Whats the status of this?

[skyace65]

@mhilbrunner I'm not working on this or the spatial material PR until the first 4.0 alpha. The whole reason I made these two PRs was I thought we were close to an alpha which turned out to be completely wrong.