Update integration test for new dartdoc URL. (#8351)

Author: isoos

pkg/pub_integration/lib/script/publishing.dart

@@ -210,7 +210,16 @@ class PublishingScript {
     if (!pageHtml.contains('made with love by dartdoc')) {
       throw Exception('Documentation page is not the output of dartdoc.');
     }
-    if (!pageHtml.contains('<a href="retry/retry-library.html">')) {
+    final retryLinks = [
+      // generated by dartdoc 8.3
+      '<a href="retry">retry</a>',
+      // maybe a future dartdoc will generate this
+      // see https://github.com/dart-lang/dartdoc/issues/3936
+      '<a href="retry/">retry</a>',
+      // generated by dartdoc 8.1
+      '<a href="retry/retry-library.html">retry</a>',
+    ];
+    if (!retryLinks.any(pageHtml.contains)) {
       throw Exception('Documentation page does not contain main library.');
     }
   }