Address example-ID warnings

Author: apasel422

index.bs

@@ -443,14 +443,14 @@ members helps ensure that, e.g., "`key1, key2`" is treated equivalently to "`key
 In the following example, only the "`trigger`" key should be interpreted by the
 recipient after the header has been parsed as a structured dictionary:
 
-<pre class="example" heading="Greased Attribution-Reporting-Eligible header">
+<pre class="example" heading="Greased Attribution-Reporting-Eligible header" id=grease-eligible>
 Attribution-Reporting-Eligible: not-event-source, trigger=event-source;navigation-source=3
 </pre>
 
 In the following example, only the "`os`" key should be interpreted by the
 recipient after the header has been parsed as a structured dictionary:
 
-<pre class="example" heading="Greased Attribution-Reporting-Support header">
+<pre class="example" heading="Greased Attribution-Reporting-Support header" id=grease-support>
 Attribution-Reporting-Support: os=web
 </pre>