[Chapel Merge] Add future to track the bug reported in #18257

Branch: refs/heads/main
Revision: 78584e5
Author: lydia-duncan
Log Message:

Merge pull request #18277 from lydia-duncan/privateModFuture

Add future to track the bug reported in #18257
[new future, not reviewed]

This test demonstrates that a private submodule is accidentally able to be
imported outside of the scope where the module is defined, if the parent module
is used. This is not intended behavior.

Based on code written by Bryant in #18257

Passed a fresh checkout

Modified Files:
A test/visibility/private/moduleSymbols/importPrivateSubmodule.bad

A test/visibility/private/moduleSymbols/importPrivateSubmodule.chpl
A test/visibility/private/moduleSymbols/importPrivateSubmodule.future
A test/visibility/private/moduleSymbols/importPrivateSubmodule.good

Compare: https://github.com/chapel-lang/chapel/compare/e41fe78a788e...78584e58bc4b