[css-images-4] Remove broken links. w3c#8707

Author: fantasai

css-images-4/Overview.bs

@@ -2441,8 +2441,8 @@ Interpolating ''stripes()'' {#interpolating-stripes}
 		first match each stripe in the start image
 		to the corresponding stripe at the same index in the end image.
 		Then, for each pair of stripes,
-		interpolate the <a href="https://www.w3.org/TR/css3-transitions/#animtype-length">thickness</a>
-		and <a href="https://www.w3.org/TR/css3-transitions/#animtype-color">color</a> independently.
+		interpolate the thickness
+		and color independently.
 
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