Adapt rgb glossary entry with info about sRGB

[teoli2003]

The RGB glossary entry didn't speak about what a color space is. On the web, the RGB color model represents a color of the sRGB color space.

This PR makes it clearer, without having two glossary entries for RGB and sRGB.

It also speaks a bit about Adobe RGB, because if you copy the components in Photoshop or Illustrator you'll get a different color on the web, as the color spaces are not identical.

This is part of openwebdocs/project#92

[github-actions]

Preview URLs

• https://pr14890.content.dev.mdn.mozit.cloud/en-US/docs/Glossary/RGB

Flaws

URL: /en-US/docs/Glossary/RGB
Title: RGB
on GitHub
Flaw count: 1

• macros:
  • /en-US/docs/Glossary/GLSL does not exist

External URLs

URL: /en-US/docs/Glossary/RGB
Title: RGB
on GitHub

• https://en.wikipedia.org/wiki/Adobe_RGB_color_space (1 time) (Note! This may be a new URL 👀)
• https://en.wikipedia.org/wiki/SRGB (1 time) (Note! This may be a new URL 👀)

(this comment was updated 2022-04-12 06:06:54.846118)

[wbamberg]

Just a couple of tiny copy edits.

[wbamberg]

Thank you @teoli2003 !