Backport PR #43468: CI: split Windows Azure tests in half#43497

jreback merged 2 commits intopandas-dev:1.3.xpandas-dev/pandas:1.3.xfrom

Dr-Irv:auto-backport-of-pr-43468-on-1.3.xDr-Irv/pandas:auto-backport-of-pr-43468-on-1.3.xCopy head branch name to clipboard