fix: add missing newline at the end of the solution files

Author: eunice-hong

contains-duplicate/eunice-hong.ts

@@ -12,4 +12,4 @@
 function containsDuplicate(nums: number[]): boolean {
   let numSet = new Set(nums);
   return numSet.size != nums.length;
-};
+};

top-k-frequent-elements/eunice-hong.ts

@@ -20,4 +20,4 @@ function topKFrequent(nums: number[], k: number): number[] {
         .sort((a, b) => b[1] - a[1]) 
         .slice(0, k)
         .map(([num, _]) => num);
-};
+};