fix: apply the booking horizon to admins as well

tests/Controller/BookingControllerTest.php

@@ -522,14 +522,21 @@ class BookingControllerTest extends WebTestCase
         self::assertStringContainsString('höchstens 3 Monate in die Zukunft', (string) $response->getContent());
     }
 
-    public function testAnAdminIsNotBoundByTheHorizon(): void
+    /**
+     * The horizon used to be lifted for ROLE_ADMIN on the grounds that an admin books for other
+     * people. They do not -- this modal always books for whoever is using it, and the admin area
+     * is read-only -- so the exemption only let an admin block a desk for themselves half a year
+     * ahead.
+     */
+    public function testAnAdminIsBoundByTheHorizonToo(): void
     {
         $this->client->loginUser($this->admin('[email protected]'));
         $beyond = BookingHorizon::latest()->modify('+2 months');
 
         $response = $this->submitBookingModal($this->resource('D1'), $beyond->format('Y-m-d'), ['allDay' => '1']);
 
-        self::assertSame(Response::HTTP_OK, $response->getStatusCode());
+        self::assertSame(Response::HTTP_UNPROCESSABLE_ENTITY, $response->getStatusCode());
+        self::assertStringContainsString('höchstens 3 Monate im Voraus', (string) $response->getContent());
     }
 
     /**