[Chapel Merge] Fix typo in Map.chpl

Branch: refs/heads/master
Revision: 801e47b
Author: bradcray
Log Message:

Merge pull request #16709 from dgarvit/map_typo

Fix typo in Map.chpl

[contributed by @dgarvit, reviewed by me]

Found this small error in documentation while going through Map.chpl when I was working on #16704.

Modified Files:
M modules/standard/Map.chpl

Compare: https://github.com/chapel-lang/chapel/compare/ce35547b67a1...801e47b93584