[Backport][v1.38.x] Source k8s test driver install script from core repo (#8573)#8599

temawi merged 1 commit intogrpc:v1.38.xgrpc/grpc-java:v1.38.xfrom

temawi:v1.38.x-xds-k8s-install-from-mastertemawi/grpc-java:v1.38.x-xds-k8s-install-from-masterCopy head branch name to clipboard