[roll] Roll fuchsia [swd-e2e-tests] Clear FFX isolate directory before creating OTA

The FFX isolate directory is removed to ensure a clean state for each
OTA build, preventing potential conflicts or issues from previous ffx
run of a different version.

Original-Bug: 498640731
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1570541
Original-Revision: c982d9b27b05bae35231f8a8b97c3263f62948a9
GitOrigin-RevId: d57f706e0c3beafd789eafcbecf3f411d313f852
Change-Id: Ieefe1eb8db3c517c8f49783bef8caf4dbe076a4a

stem

diff --git a/stem b/stem
index a307077..c04bb68 100644
--- a/stem
+++ b/stem
@@ -8,6 +8,6 @@
             manifest="manifests/platform"
             root=""
             remote="https://fuchsia.googlesource.com/fuchsia"
-            revision="8770340bcbffcfbf56eaaf904c63e31477711324"/>
+            revision="c982d9b27b05bae35231f8a8b97c3263f62948a9"/>
   </imports>
 </manifest>