Update Security String to 2021-11-01 am: bdb63576ff am: 51b1e117c7

Original change: https://googleplex-android-review.googlesource.com/c/platform/build/+/15845733

Change-Id: I03c662f3d629a85488189aaf39acd0708ba90f5c
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index b5c9d18..bdf9d0b 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 := 2021-10-01
+      PLATFORM_SECURITY_PATCH := 2021-11-01
 endif
 .KATI_READONLY := PLATFORM_SECURITY_PATCH