[Chapel Merge] Use large problem size in the auto-aggregated inde

Branch: refs/heads/master
Revision: 8e67fc5
Author: e-kayrakli
Log Message:

Merge pull request #17408 from e-kayrakli/ig-auto-agg-probsize

Use large problem size in the auto-aggregated indexgather

When I created this test, I just used the execopts for the unoptimized version
which is too small for CS. It causes a big difference between the manual and
auto aggregated versions:


This PR makes the auto-aggregated version always use the large problem size.

[Reviewed by @ronawho]

Modified Files:
M test/studies/bale/indexgather/ig-auto-agg.ml-execopts

Compare: https://github.com/chapel-lang/chapel/compare/4565ae7a92f6...8e67fc506093