Convert `checksRunsSelected` state from array to set

Release-Notes: skip
Change-Id: Icaf33559fe3b4e924a2514ed8debcabbc95a8204
diff --git a/polygerrit-ui/app/elements/core/gr-router/gr-router_test.ts b/polygerrit-ui/app/elements/core/gr-router/gr-router_test.ts
index 5c5e67d..119ba48 100644
--- a/polygerrit-ui/app/elements/core/gr-router/gr-router_test.ts
+++ b/polygerrit-ui/app/elements/core/gr-router/gr-router_test.ts
@@ -1161,7 +1161,7 @@
             attempt: 1,
             filter: 'fff',
             tab: 'checks',
-            checksRunsSelected: ['asdf', 'qwer'],
+            checksRunsSelected: new Set(['asdf', 'qwer']),
             checksResultsFilter: 'asdf.*qwer',
           });
         });