BUG: fix itkPeriodicBoundaryConditionTest itkGradientImageFilterTest#128

hjmjohnson wants to merge 1 commit intoInsightSoftwareConsortium:masterInsightSoftwareConsortium/ITK:masterfrom

hjmjohnson:FixPeriodicBoundaryConditionTestFailurehjmjohnson/ITK:FixPeriodicBoundaryConditionTestFailureCopy head branch name to clipboard