Update .problemList.json

Author: neetcode-gh

.problemList.json

@@ -319,6 +319,11 @@
           "https://leetcode.com/problems/best-time-to-buy-and-sell-stock/",
           "0121"
        ],
+       [
+          "Number of Sub Arrays of Size K and Avg Greater than or Equal to Threshold",
+          "https://leetcode.com/problems/number-of-sub-arrays-of-size-k-and-average-greater-than-or-equal-to-threshold/",
+          "1343"
+       ],
        [
           "Longest Substring Without Repeating Characters",
           "https://leetcode.com/problems/longest-substring-without-repeating-characters/",