fix PR checklist formatting

Author: sharanabasava-05

sorts/bubble_sort.py

@@ -50,7 +50,7 @@ def bubble_sort_iterative(collection: list[Any]) -> list[Any]:
 
     Pure implementation of bubble sort algorithm in Python
     :param collection:....
-    :return:...
+    :return:....
 
     Time Complexity:
         Best Case: O(n)