PHPC-2413: Use new distros for RHEL ppc and Z#1647

alcaeus merged 1 commit intomongodb:v1.19mongodb/mongo-php-driver:v1.19from

alcaeus:phpc-2413-migrate-evergreen-distrosalcaeus/mongo-php-driver:phpc-2413-migrate-evergreen-distrosCopy head branch name to clipboard