[FeedbackText]: Add correct color variables for error and valid statuses

[ly-tempel-bitweb]

Problem

In dark mode, the color of feedback text is white for error and valid statuses, but it should be red and green accordingly.

Solution

Change colors to color: var(--form-general-feedback-error-text); and color: var(--form-general-feedback-success-text);.

Examples and information

Figma