Migrate manywheel and conda Docker build from centos:7 to pypa/manylinux2014_x86_64

[atalman]

We would need to migrate our Docker builds to later version of centos:7 since its approaching end of life in 1 year.

CentOS-7 updates until June 30, 2024:
https://wiki.centos.org/FAQ/General#What_is_the_support_.27.27end_of_life.27.27_for_each_CentOS_release.3F

Following Docker builds:

builder/manywheel/Dockerfile

Line 5 in bb821d4

ARG GPU_IMAGE=centos:7

builder/conda/Dockerfile

Line 3 in bb821d4

FROM centos:7 as base

builder/manywheel/build_docker.sh

Line 20 in bb821d4

GPU_IMAGE=centos:7

...

Hence we should migrate to:
https://quay.io/repository/pypa/manylinux2014_x86_64?tab=tags&tag=latest
as @malfet suggested

cc : @malfet @seemethere @jeffdaily

[malfet]

But centos:8 already EOLed in 2021, see https://www.centos.org/centos-linux-eol/
IMO we should migrate Linux docker base to https://github.com/pypa/manylinux / https://quay.io/repository/pypa/manylinux2014_x86_64?tab=tags&tag=latest