[roll] Roll fuchsia [ffx] minor tech cleanups

While trying to carefully go through the connection flow,
I noticed that we are sometimes returning Result from code
that cannot fail, so I cleaned those up.  I also noted
that the error produced for some connectivity errors confusingly
referred to a "matcher", which is a term we don't use elsewhere.

Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1255245
Original-Revision: 86c6adf2b42a5af3408e2cab2da756dcd557e2c9
GitOrigin-RevId: dee1335492331ad040cd75b2ff8468c4170ff0f0
Change-Id: I861a077af9dbf55bb4f357eeef0f7daabfec445d
diff --git a/stem b/stem
index 6da35a6..deed422 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="3e2d9714af2e6d589d0f208dcd79325c4e96421d"
+             revision="86c6adf2b42a5af3408e2cab2da756dcd557e2c9"
              />
   </projects>
   <hooks>