[roll] Roll fuchsia [realm_proxy] Migrate to new Open signature

Original-Bug: 378924259
Test: fx test //src/testing/realm_proxy
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1209886
Original-Revision: 1d9ac5afe31bcedb9ba4239726ab9c83a89e53e0
GitOrigin-RevId: 86cab6133b5489a8132840326a57e544521bf988
Change-Id: I3b88fc4f633e2130882476c0ec2afde1c3be02fe
diff --git a/stem b/stem
index 7d061cd..c362939 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="5f143fbb40166cb7885079eb6cfc45d772287a7d"/>
+             revision="1d9ac5afe31bcedb9ba4239726ab9c83a89e53e0"/>
   </projects>
   <hooks>
     <hook name="install-environment"