[css-color] Tests assume old hsl()/hsla() clipping behavior or depend on unclear gamut mapping to sRGB (#45941)
Removes tests that were assuming the CSS Color 3 rules for hsl()/hsla()
where lightness and saturation values outside of 0-100 were clamped to
that range. CSS Color 4 states that only saturation below 0 is clamped.
To make it clear that only the saturation clamping is being tested, the
tests where that is still tested have been renamed to be more clear.