feat(content): hidden test cases

backend/data/questions/min-cost-climbing-stairs.yaml

@@ -26,6 +26,12 @@ test_cases:
       expected: 10
     - input: { cost: [1, 100] }
       expected: 1
+    - input: { cost: [1, 2, 3] }
+      expected: 2
+    - input: { cost: [0, 1, 2, 3, 4, 5] }
+      expected: 6
+    - input: { cost: [5, 5, 5, 5, 5] }
+      expected: 15
 
 description: |
   You are given an integer array `cost` where `cost[i]` is the cost of the i<sup>th</sup> step on a staircase. Once you pay the cost, you can either climb one or two steps.