fix(GlPath): Keep path text white in dark mode

What does this MR do?

Fix gitlab#351627 (closed)

Keep path text #fff in dark mode. Remove background color.

Screenshots of active / hovered / disabled / inactive path:

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Does this MR meet the acceptance criteria?

Conformity

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Accessibility

If this MR adds or modifies a component, take a few moments to review the following:

• Color combinations have sufficient contrast.