[roll] Roll third_party/pigweed pw_bluetooth_sapphire: Fix UBSAN failures in l2cap fuzz tests

Don't call memcpy with nullptrs.

Original-Bug: 393957973
Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/278455
Tests-Not-Needed: Josh Conner <[email protected]>
Presubmit-Verified: CQ Bot Account <[email protected]>
Original-Revision: 8dab133797b53ee89b2aad7304325983242dae7f
GitOrigin-RevId: 96ae30cf9595cb15940bb10ab00b8a9373a2a7e8
Change-Id: I06db08983874026c16ec953287531c2fa4a7f1e8

Author: Josh Conner

third_party/flower

@@ -512,7 +512,7 @@
              path="third_party/pigweed/src"
              remote="https://fuchsia.googlesource.com/third_party/pigweed.googlesource.com/pigweed/pigweed"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="2861b6ad5f94c2c8b4b393761d93c568eef9547e"/>
+             revision="8dab133797b53ee89b2aad7304325983242dae7f"/>
     <project name="third_party/github.com/google/python_portpicker"
              gitsubmoduleof="fuchsia"
              path="third_party/python_portpicker/src"