Update percolate-query.asciidoc

Add missing callout to percolate query

docs/reference/query-dsl/percolate-query.asciidoc

@@ -341,6 +341,8 @@ This will yield the following response.
 --------------------------------------------------
 // TESTRESPONSE[s/"took": 7,/"took": "$body.took",/]
 
+<1> The terms from each query have been highlighted in the document.
+
 Instead of the query in the search request highlighting the percolator hits, the percolator queries are highlighting
 the document defined in the `percolate` query.