[roll] Roll fuchsia [power][storage] Create system integration test

This change adds the system integration directory with a test created
for storage. This test includes a custom product and board that infra
will flash onto a vim3 device and then run the test in isolation. The
custom product is a bootstrap level product, so it will be run on
bringup builders.

Original-Bug: 335526421
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1042046
Original-Revision: 64d2b1b3a1b5576668e8abab0e20ce2f131c0c61
GitOrigin-RevId: fa4c8253377f9f7a9a92447cf146de1ae3521fff
Change-Id: If114e08e0032316681585fca24a25fe25e2026e9
diff --git a/stem b/stem
index 3fa9d30..0d0894a 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="514341a2c6141b3a3e95b82197eac5f917ec00e1"/>
+             revision="64d2b1b3a1b5576668e8abab0e20ce2f131c0c61"/>
   </projects>
   <hooks>
     <hook name="install-environment"