[Chapel Merge] Bump timeout of stencil-serial perf test

Branch: refs/heads/main
Revision: 1fc544f473333239d4e507676b43f2af59331dfb
Author: bradcray
Link: Bump timeout of stencil-serial perf test by bradcray · Pull Request #28715 · chapel-lang/chapel · GitHub
Log Message:
Bump timeout of stencil-serial perf test (#28715)

[trivial, not reviewed]

This test runs very close to the default 5-minute timeout on 1-node EX
performance testing, so here I'm bumping the timeout up to 500 seconds
to give it a bit more breathing room.

Resolves https://github.com/Cray/chapel-private/issues/7738

Compare: Comparing 88ac9116e77dd82e5dd8877993351ef9f731cc29...7beeeec9b1a694702209651339455fc96c526520 · chapel-lang/chapel · GitHub

Diff:
A test/studies/prk/Stencil/stencil-serial.perftimeout
https://github.com/chapel-lang/chapel/pull/28715.diff