CQ update

  - swap the N5 experiment over to the new GN N5 bot

  - cut down on the Windows build duplication: the other two bots
    cover x86, x86-64, Release, Debug, _and_ Vulkan already.

  - remove the Release-Shared tester: I added this bot to act as a proxy
    for the also Shared-build Android bots, but 1) they're fast enough
    to no longer need a proxy (see N5 above) and 2) they're no longer
    Shared builds.  I intend to completely drop support for dm and
    nanobench in Shared builds, so this bot will not just drop from the
    CQ but completely disappear.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2346463002

Review-Url: https://codereview.chromium.org/2346463002
1 file changed