[css-color-5][editorial] remove duplicate id

Author: svgeesus

css-color-5/Overview.bs

@@ -860,11 +860,11 @@ The origin color and the relative color need not use the same color function.
 <dfn export>Required conversion</dfn>:
 All operations take part in the 
 [=color space=] of the [=relative color=] function;
-<span id="required-conversion">if the
+if the
 <dfn export>originally specified color space</dfn>
 for the [=origin color=] used a different color function,
 it's first converted into the chosen color function,
-so it has meaningful values for the components</span>
+so it has meaningful values for the components,
 and [=component keywords=] 
 refer to the color space of the relative color,
 <em>not</em> the [=origin color=].