FIX: remove word boundary regex (\b) for search result highlights. (#9338)

test/javascripts/acceptance/search-test.js

@@ -94,13 +94,13 @@ QUnit.test("Search with context", async assert => {
 
   const highlighted = [];
 
-  find("#post_7 span.highlight-strong").map((_, span) => {
+  find("#post_7 span.highlighted").map((_, span) => {
     highlighted.push(span.innerText);
   });
 
   assert.deepEqual(
     highlighted,
-    ["a", "a", "proper", "a"],
+    ["a proper"],
     "it should highlight the post with the search terms correctly"
   );