Bump Security String to 2021-12-05

Implemented:
============
CVE:            References:  Type:  Severity:  Updated AOSP versions:
CVE-2021-0952   A-195748381  ID     High       9, 10, 11, 12
CVE-2021-0954   A-143559931  EoP    High       10, 11
CVE-2021-0955   A-192085766  EoP    High       11
CVE-2021-0956   A-189942532  EoP    Critical   11, 12
CVE-2021-0958   A-200041882  DoS    Moderate   11, 12
CVE-2021-0963   A-199754277  EoP    High       9, 10, 11, 12
CVE-2021-0964   A-193363621  ID     High       9, 10, 11, 12
CVE-2021-0965   A-194300867  EoP    High       9, 10, 11, 12
CVE-2021-0966   A-198346478  ID     High       11, 12
CVE-2021-0967   A-199065614  ID     High       10, 11, 12
                             RCE    Critical   9
CVE-2021-0968   A-197868577  RCE    Critical   9, 10, 11, 12
CVE-2021-0969   A-199922685  DoS    Moderate   10, 11
CVE-2021-0971   A-188893559  ID     High       9, 10, 11, 12
CVE-2021-0704   A-179338675  ID     High       9, 10, 11
CVE-2021-0970   A-196970023  EoP    High       9, 10, 11, 12

Previously Implemented:
=======================
CVE:            References:  Type:  Severity:  Updated AOSP versions:
Prior Change:

Not Implemented:
================
None

Not Applicable (platform source):
=================================
CVE:            References:  Type:  Severity:  Updated AOSP versions:
CVE-2021-0953   A-184046278  EoP    High       9, 10, 11, 12 (we don't sync quicksearchbox)

Change-Id: Ia42c0565696cae3dbf80a7152e0e61b61a1fa6cb

core/version_defaults.mk

@@ -240,7 +240,7 @@ ifndef PLATFORM_SECURITY_PATCH
     #  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 := 2021-11-05
+      PLATFORM_SECURITY_PATCH := 2021-12-05
 endif
 .KATI_READONLY := PLATFORM_SECURITY_PATCH