Implement new Gray scale on Claro

Problem/Motivation

Right now we have a limited amount of greys on the design system and they don't have enough middle steps for some situations. Also, some of them have a different tone due to the grow of the design system.

Proposed resolution

Implement the redesigned grey scale with the newly defined colors and adjust existing colors.

Also it should be discussed which color we should finally use for the disabled elements.

Link to Figma specs: https://www.figma.com/file/OqWgzAluHtsOd5uwm1lubFeH/Drupal-Design-system...

Remaining tasks

• Define new color values
• Update color values
• Replace existing colors
• Change variable names

User interface changes

All grey colors will change.

Release notes snippet