[Chapel Merge] Adjust this test to use operator methods

Branch: refs/heads/main
Revision: 7dcec7e
Author: lydia-duncan
Log Message:

Merge pull request #18411 from lydia-duncan/opMethodOOB

Adjust this test to use operator methods
[reviewed by @dlongnecke-cray]

I'd accidentally run it in a mode it wasn't supposed to run in when I tried to
use operator methods earlier, having missed that there was a skipif for
CHPL_COMM==none. Running with gasnet, the change works fine.

Resolves #17834

Checked a fresh checkout

Modified Files:
M test/library/standard/Set/setCommTest.chpl

Compare: https://github.com/chapel-lang/chapel/compare/15f1d5f9cc05...7dcec7e9883c