Update Security String to 2021-03-01 am: 0e3ba7d2f7 am: e1380bb1df

Original change: https://googleplex-android-review.googlesource.com/c/platform/build/+/13318721

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I4b3187f2211c7f7f5dd6a766b2d27224dea986ac
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 9b061f3..a6347a1 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 := 2021-02-01
+      PLATFORM_SECURITY_PATCH := 2021-03-01
 endif
 .KATI_READONLY := PLATFORM_SECURITY_PATCH