fix: Remove SVG hover fill (#9340)

This causes our company logo to turn white on hover: https://docs.unity3d.com/Packages/com.unity.render-pipelines.high-definition@12.1/api/UnityEngine.Rendering.HighDefinition.AmbientOcclusion.html

Author: RobJessop

templates/default/styles/docfx.css

@@ -111,10 +111,6 @@ span.languagekeyword{
     font-weight: bold;
 }
 
-svg:hover path {
-    fill: #ffffff;
-}
-
 .hljs {
   display: inline;
   background-color: inherit;