[roll] Roll fuchsia [feedback] Remove unused config flags

The values for these config flags are the same in all configurations,
and have been the same for at least several years. Instead of migrating
the flags to domain config, just remove them.

The flags are:

- persisted_logs_num_files
- persisted_logs_total_size_kib

Original-Bug: 457485424
Test: `fx test //src/developer/forensics`
Test: `fx shell crasher` @ 82a879ca1f3c522a
[g-review]

Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1434174
Original-Revision: 8f1b28950c556f26ecb217ff98d1fa0c3b4d52e5
GitOrigin-RevId: c431512ad42b1e194aa7bc369157d4a96bac2f0a
Change-Id: Idd45347eaefdbfca482d23329a9c6bb4ce032127
diff --git a/stem b/stem
index fa47574..3aa8670 100644
--- a/stem
+++ b/stem
@@ -7,7 +7,7 @@
             manifest="manifests/platform"
             root=""
             remote="https://fuchsia.googlesource.com/fuchsia"
-            revision="f56d26650be738bb45aceba59763aa0d5b841cbb"/>
+            revision="8f1b28950c556f26ecb217ff98d1fa0c3b4d52e5"/>
   </imports>
   <projects>
     <project name="cobalt"