Remove activity timeout-overdue rollup self-skip on Waterline dashboard test

Drops the markTestSkipped branch in
V2DashboardStatsControllerTest::testIndexExposesActivityTimeoutOverdueRollup.
The workflow rollout-safety contract triple
(operator_metrics.activities.{timeout_overdue,oldest_timeout_overdue_at,max_timeout_overdue_age_ms})
ships in published workflow alpha 2.0.0-alpha.21, which Waterline's
composer install resolves for durable-workflow/workflow: ^2.0@dev.

Each key is now asserted unconditionally with assertArrayHasKey,
matching the matching-role / dispatch-overdue / run-wait / stuck-lease /
ready-due / claim-failed / retrying-activity / dispatch-failed /
run-summary missing-age / backend-severity removal pattern, so a rename
or drop fails CI loudly instead of silently self-skipping.

Author: durable-workflow-ops

tests/Feature/V2DashboardStatsControllerTest.php

@@ -1006,15 +1006,9 @@ public function testIndexExposesActivityTimeoutOverdueRollup(): void
         $activities = $response->json('operator_metrics.activities');
 
         $this->assertIsArray($activities);
-
-        if (! array_key_exists('timeout_overdue', $activities)
-            || ! array_key_exists('oldest_timeout_overdue_at', $activities)
-            || ! array_key_exists('max_timeout_overdue_age_ms', $activities)) {
-            $this->markTestSkipped(
-                'Vendored workflow package predates the activity timeout-overdue rollup '
-                . '(operator_metrics.activities.{timeout_overdue,oldest_timeout_overdue_at,max_timeout_overdue_age_ms}).',
-            );
-        }
+        $this->assertArrayHasKey('timeout_overdue', $activities);
+        $this->assertArrayHasKey('oldest_timeout_overdue_at', $activities);
+        $this->assertArrayHasKey('max_timeout_overdue_age_ms', $activities);
 
         $this->assertIsInt($activities['timeout_overdue']);
         $this->assertGreaterThanOrEqual(0, $activities['timeout_overdue']);