clear some typos in comments

Author: peterpanmj

pandas/_libs/algos_rank_helper.pxi.in

@@ -86,7 +86,7 @@ def rank_1d_{{dtype}}(object in_arr, ties_method='average', ascending=True,
     mask = values == iNaT
     {{endif}}
 
-    # doulbe sort first by mask and then by values to ensure nan values are
+    # double sort first by mask and then by values to ensure nan values are
     # either at the beginning or the end. mask/(~mask) controls padding at
     # tail or the head
     {{if dtype != 'uint64'}}