test: drop unused timer globals from the dashboard sandbox

ESLint's test config does not declare setTimeout and friends, so passing
them into the vm sandbox failed the Lint job. Nothing the test exercises
uses them.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

test/dashboard-ui.test.js

@@ -49,10 +49,6 @@ function loadFilters() {
     localStorage: { getItem: () => null, setItem() {} },
     navigator: { language: "en-US" },
     console,
-    setTimeout,
-    clearTimeout,
-    setInterval,
-    clearInterval,
   };
   sandbox.window = sandbox;
   vm.createContext(sandbox);