uniquePaths = (row, col) => {
    const isBaseCase = ((row == 1) || (col == 1));
    if (isBaseCase) return 1;

    return dfs(row, col);/* Time O(2^N) | Space O(HEIGHT) */
}
Brute Force - DFS
Time O(2^N) | Space O(HEIGHT)
https://leetcode.com/problems/unique-paths/
@param {number} m
@param {number} n
@return {number}