feat(content): hidden test cases

backend/data/questions/product-of-array-except-self.yaml

@@ -25,6 +25,12 @@ test_cases:
       expected: [0, 0]
     - input: { nums: [5, -2, 4] }
       expected: [-8, 20, -10]
+    - input: { nums: [1, 2, 3, 4, 5] }
+      expected: [120, 60, 40, 30, 24]
+    - input: { nums: [0, 1, 2, 3] }
+      expected: [6, 0, 0, 0]
+    - input: { nums: [-1, -1, -1] }
+      expected: [1, 1, 1]
 
 description: |
   Given an integer array `nums`, return an array `answer` such that `answer[i]` is equal to the product of all the elements of `nums` except `nums[i]`.