feat(color): Add srgb_rec709_display as a built-in color space

[brechtvl]

Description

srgb_rec709_display is now a built-in color space alongside srgb_rec709_scene, and config color spaces like "sRGB - Display" are now classified as such. The built-in sRGB name remains an alias of srgb_rec709_scene.

This means it can be relied on to be available, even when using an OCIO config that does not contain it. And is on equal footing with srgb_rec709_scene in case it becomes the default in the future.

Tests

Added some tests to detect the presence of this.

Warning

The test output will change and need to be updated after #4971 or #5387 lands, as it will then find the matching color space in older configs.

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[brechtvl]

CC @zachlewis

This is the last of my own changes I currently hope to get into 3.2, to make the display interop ID support somewhat complete. In the sense that when it's encountered from e.g. a user input or colorInteropID it should work equally well as the corresponding scene referred interop ID, but without yet making it the default guess when reading files.