[css-speech-1] Fix markup error from Bikeshed conversion w3c#5222

Author: fantasai

css-speech-1/Overview.bs

@@ -627,7 +627,7 @@ The 'pause' shorthand property</h3>
 
 	<pre class=propdef>
 	Name: pause
-	Value: &lt;'pause-before'&gt; &lt;'pause-after'&gt;?
+	Value: <<'pause-before'>> <<'pause-after'>>?
 	Initial: N/A (see individual properties)
 	Applies to: all elements
 	Inherited: no
@@ -734,7 +734,7 @@ The 'rest' shorthand property</h3>
 
 	<pre class=propdef>
 	Name: rest
-	Value: <'rest-before'> <'rest-after'>?
+	Value: <<'rest-before'>> <<'rest-after'>>?
 	Initial: N/A (see individual properties)
 	Applies to: all elements
 	Inherited: no
@@ -891,7 +891,7 @@ The 'cue' shorthand property</h3>
 
 	<pre class=propdef>
 	Name: cue
-	Value: <'cue-before'> <'cue-after'>?
+	Value: <<'cue-before'>> <<'cue-after'>>?
 	Initial: N/A (see individual properties)
 	Applies to: all elements
 	Inherited: no