Fix isort errors

Author: shan7030

scheduling/round_robin.py

@@ -3,8 +3,8 @@
 In Round Robin each process is assigned a fixed time slot in a cyclic way.
 https://en.wikipedia.org/wiki/Round-robin_scheduling
 """
-from typing import List
 from statistics import mean
+from typing import List
 
 
 def calculate_waiting_times(burst_times: List[int]) -> List[int]:

scheduling/shortest_job_first.py

@@ -4,6 +4,7 @@
 Please use spaces to separate times entered.
 """
 from typing import List
+
 import pandas as pd