Skip SkSLSwitchDefaultOnly_GPU in IntelIrisXe jobs

Change-Id: I9979d8b27d1fdeadde1066428cc1837459dceca6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/585605
Commit-Queue: James Godfrey-Kittle <jamesgk@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
2 files changed