[Chapel Merge] Fix bug with importing private submodules

Branch: refs/heads/main
Revision: cf32ab1
Author: lydia-duncan
Link: Unavailable
Log Message:

Merge pull request #19671 from lydia-duncan/fixPrivateBleed

Fix bug with importing private submodules
[reviewed by @vasslitvinov]

The resolution of import/use statements was failing to consider whether the
symbol it was matching against was private to the module in which it was found
via a use/import chain. This adjusts ResolveScope::followImportUseChains to
skip including symbols that are private.

Resolves #18257
Resolves #14535

Passed a full paratest with futures

Modified Files:
R test/modules/vass/use-a-Math-function.bad

R test/modules/vass/use-a-Math-function.future
R test/visibility/private/moduleSymbols/importPrivateSubmodule.bad
R test/visibility/private/moduleSymbols/importPrivateSubmodule.future
M compiler/passes/ResolveScope.cpp

Compare: https://github.com/chapel-lang/chapel/compare/91b79ddd69dd...cf32ab107109