[Chapel Merge] Fix some issues with OrderedMap

Branch: refs/heads/master
Revision: bfc0a0a
Author: e-kayrakli
Log Message:

Merge pull request #17450 from e-kayrakli/orderedMap-fixes

Fix some issues with OrderedMap

This is a follow up to Add module OrderedMap by Rapiz1 · Pull Request #16271 · chapel-lang/chapel · GitHub and
should be merged after that.

Fixes 3 issues with OrderedMap:

  • Update a good file with the improved compiler error message
  • Fix a type mismatch between the internal _set field and the value assigned
    to it inside the initializer
  • Remove unnecessary proc < workarounds

Trivial, not reviewed.