Update Security String to 2021-03-01

Bug: 177091143
Change-Id: I7cfed298cb518d150ea1f944b57504f9b4578a7b
Merged-In: I6d6542306c51ac1682f02cbce6701688d2bdbea2
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 07f19dd..f99e806 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -181,7 +181,7 @@
     #  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
 
 ifndef PLATFORM_BASE_OS