Test: Increase timeout for flaky webWorker.html

This runs the entire test/main test suite as a single test.
Since 3c2b768 enabled a default
timeout of 3s, this has sometimes timed out in GitHub Actions.

It completed locally in about 0.9s, but a bit longer seems reasonable
for such a large test suite.

test/webWorker.js

@@ -2,7 +2,7 @@
 QUnit.module('Web Worker');
 
 QUnit.test('main tests', function (assert) {
-  assert.expect(1);
+  assert.timeout(10000);
   var done = assert.async();
   var worker = new Worker('webWorker-worker.js');