manifest: Update sdk-zephyr revision (auto-manifest PR)

Automatically created by action-manifest-pr GH action from PR:
nrfconnect/sdk-zephyr#3994

Signed-off-by: Nordic Builder <pylon@nordicsemi.no>

Author: NordicBuilder

west.yml

@@ -65,7 +65,7 @@ manifest:
     # https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/guides/modules.html
     - name: zephyr
       repo-path: sdk-zephyr
-      revision: d947269643dd51e4e95d35d148cecb40562fe0d2
+      revision: pull/3994/head
       import:
         # In addition to the zephyr repository itself, NCS also
         # imports the contents of zephyr/west.yml at the above