Make the AMD ABL regtest stable on GPUs

[moprak-nrel]

Summary

Perturb temperature/velocity values so that the regtest values aren't too small for SGS terms. Currently the alpha_eff is close to machine precision leading to flaky regtest runs on GPUs.

Pull request type

Please check the type of change introduced:

• [ ] Bugfix
• [ ] Feature
• [ ] Code style update (formatting, renaming)
• [ ] Refactoring (no functional changes, no api changes)
• [ ] Build related changes
• [ ] Documentation content changes
• [x] Other (please describe): update regtest parameters

Checklist

The following is included:

• [ ] new unit-test(s)
• [ ] new regression test(s)
• [ ] documentation for new capability

This PR was tested by running:

• the unit tests
  • [ ] on GPU
  • [ ] on CPU
• the regression tests
  • [x] on GPU
  • [x] on CPU

Additional background

Issue Number: