Chore: Relocate tooltip 'error status' styling to tooltip.scss

[Viveur]

Description

Minor alteration that makes the tooltip 'error state' styling a modifier, (eg: .tooltip--error, in line with others, such as .tooltip--position-top), and places it inside of tooltip.scss, rather than one tooltip class existing separately.

It also updates the placement of the tooltip by a few pixels, by calculating --caret-size, in a simlar manner to.tooltip--position-top

Related to #5780

Yes, I have read and understand the CONTRIBUTING.md document in this repository.

Type of change

• [ ] Chore (non-breaking change which does not add functionality)

Checklist:

• [ ] Existing test suite passes locally with my changes