[TASK] Add missing test case for fetching none existing tea

Dedicated test cases were added in the past.
This test case was not added yet.

Resolves: #858

Tests/Functional/Domain/Repository/Product/TeaRepositoryTest.php

@@ -66,6 +66,16 @@ public function findAllSortsByTitleInAscendingOrder(): void
         self::assertSame(2, $result->current()->getUid());
     }
 
+    /**
+     * @test
+     */
+    public function findByUidForInexistentRecordReturnsNull(): void
+    {
+        $model = $this->subject->findByUid(1);
+
+        self::assertNull($model);
+    }
+
     /**
      * @test
      */