[Chapel Merge] Fix a comment that wants to be helpful but is misl

Branch: refs/heads/main
Revision: d6fa829
Author: e-kayrakli
Link: Unavailable
Log Message:

Merge pull request #20384 from e-kayrakli/gpu-test-comment-fix

Fix a comment that wants to be helpful but is misleading

I added comments to a complicated kernel launch test while switching to
GPUDiagnostics-based testing. I thought I understood what's happening, but I was
wrong. I spent some time understanding what's going on today again, but couldn't
because of the comments I added. Thanks @daviditen for the explanation.

[Trivial, not reviewed]

Modified Files:
M test/gpu/native/kernelFnCalls/fnWithForall.chpl

Compare: https://github.com/chapel-lang/chapel/compare/b96122bc3556...d6fa829809c8