Update rustdoc test

Author: GuillaumeGomez

src/test/rustdoc/keyword.rs

@@ -4,7 +4,8 @@
 
 // @has foo/index.html '//h2[@id="keywords"]' 'Keywords'
 // @has foo/index.html '//a[@href="keyword.match.html"]' 'match'
-// @has foo/index.html '//div[@class="block items"]//a/@href' '#keywords'
+// @has foo/index.html '//div[@class="sidebar-elems"]//li/a' 'Keywords'
+// @has foo/index.html '//div[@class="sidebar-elems"]//li/a/@href' '#keywords'
 // @has foo/keyword.match.html '//a[@class="keyword"]' 'match'
 // @has foo/keyword.match.html '//span[@class="in-band"]' 'Keyword match'
 // @has foo/keyword.match.html '//section[@id="main"]//div[@class="docblock"]//p' 'this is a test!'