[roll] Roll fuchsia [auth] Default to use gcert where possible

FX_BUILD_AUTO_AUTH (env) controls whether or not to
auto-detect LOAS credentials type and use gcert for
auto-renewing OAuth tokens.

Was: opt-in with FX_BUILD_AUTO_AUTH=1
Now: opt-out with FX_BUILD_AUTO_AUTH=0

Original-Bug: 342026853
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1173474
Original-Revision: 345a1f1602aa83851723bd130b881850b2820f4f
GitOrigin-RevId: b634c9f96ab49434edad42ed2b67de2952b43e2f
Change-Id: Ib457bb668347834df8205cc5420242b24f2504d3
diff --git a/stem b/stem
index cf732c5..6a1dfae 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="a8b35bf6a3ea59fe8a745066e4ce3bfde3f47325"/>
+             revision="345a1f1602aa83851723bd130b881850b2820f4f"/>
   </projects>
   <hooks>
     <hook name="install-environment"