[roll] Roll fuchsia [virtio-gpu-display] Update testing docs.

This CL switches our manual testing methodology from the deprecated core
product to the supported workbench_eng product.

Test: Booted workbench_eng.x64 on qemu
Test: ffx target ssh display-tool squares
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1155914
Original-Revision: 72360d025bcd9f6ba57d19aee82c3b841c15c970
GitOrigin-RevId: e7d8ee92f781f3129fedf6aae73149df15d1e037
Change-Id: Ic1b6c2a5b0431a24b82f8904605fd0ce9cc45bf3
diff --git a/stem b/stem
index 78e56dc..5347a4a 100644
--- a/stem
+++ b/stem
@@ -11,7 +11,7 @@
              githooks="integration/git-hooks"
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="955ef74330fbe243c04d4a4d8293c237550116d9"/>
+             revision="72360d025bcd9f6ba57d19aee82c3b841c15c970"/>
   </projects>
   <hooks>
     <hook name="install-environment"