[roll] Roll fuchsia [memory] Cancel task before changing duration.

We need to cancel the prior task before scheduling a new one when notified
about a change in the memory pressure level so that the Digest will be
printed to the log.

Test: N/A
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/541743
Original-Revision: 1124973b5b65cda94127abb54260679781db2d22
GitOrigin-RevId: 4fa0b450f56084f19edc687d36988e55aca17909
Change-Id: Ia324baa5097b55d5e03fc4fc2a2ac3c6b7d602fe
diff --git a/stem b/stem
index ddc62be..07121af 100644
--- a/stem
+++ b/stem
@@ -10,7 +10,7 @@
              githooks=""
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="3f318eb8792188aa12fe26be23de6aa3f3c29ce0"/>
+             revision="1124973b5b65cda94127abb54260679781db2d22"/>
   </projects>
   <hooks>
     <hook name="install-environment"