[aarch64-port-dev ] git: openjdk/aarch64-port: master: 8274083: Update testing docs to mention tiered testing

[Aleksey Shipilev]

Changeset: 971aa353
Author:    Aleksey Shipilev <shade at openjdk.org>
Date:      2021-09-24 09:03:33 +0000
URL:       https://git.openjdk.java.net/aarch64-port/commit/971aa353aae51222ca33ebfdd61b91672a6c871a

8274083: Update testing docs to mention tiered testing

Reviewed-by: dholmes, jiefu, stuefe, ihse, mseledtsov, alanb

! doc/testing.html
! doc/testing.md