[CHERRYPICK ONLY] Update Security String to 2019-10-06

Bug:139434268
(cherry picked from commit 74684f036c6937d5270380f33e19d153c85f366a)

Change-Id: I975f5e687a4ba65437860f0ca69dd864f5d2677c
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index b803ff8..08ffb1a 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -250,7 +250,7 @@
     #  It must be of the form "YYYY-MM-DD" on production devices.
     #  It must match one of the Android Security Patch Level strings of the Public Security Bulletins.
     #  If there is no $PLATFORM_SECURITY_PATCH set, keep it empty.
-      PLATFORM_SECURITY_PATCH := 2019-11-05
+      PLATFORM_SECURITY_PATCH := 2019-10-06
 endif
 .KATI_READONLY := PLATFORM_SECURITY_PATCH