Align 'Anonymous' to 'anonymous' on cross origin setting

[wouterlucas]

Even though minor browsers can be finicky, especially on older devices. Lets align this:
https://github.com/lightning-js/renderer/blob/main/src/core/textures/ImageTexture.ts#L139

with anonymous per:
https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/crossorigin#anonymous

As pointed out in this thread:
#489 (comment)