Bump Security String to 2021-09-05

Implemented:
============
CVE:            References:  Type:  Severity:  Updated AOSP versions:
CVE-2021-0595   A-177457096  EoP    High       8.1, 9, 10, 11
CVE-2021-0598   A-180422108  EoP    High       8.1, 9, 10, 11
CVE-2021-0644   A-181053462  ID     High       10, 11
CVE-2021-0682   A-159624555  ID     High       8.1, 9, 10, 11
CVE-2021-0683   A-185398942  EoP    High       8.1, 9, 10, 11
CVE-2021-0684   A-179839665  EoP    High       8.1, 9, 10, 11
CVE-2021-0686   A-177927831  ID     High       10, 11
CVE-2021-0687   A-188913943  DoS    Critical   8.1, 9, 10, 11
CVE-2021-0688   A-161149543  EoP    High       8.1, 9, 10, 11
CVE-2021-0689   A-190188264  ID     High       8.1, 9, 10, 11
CVE-2021-0690   A-182152757  ID     High       8.1, 9, 10, 11
CVE-2021-0692   A-179289753  EoP    High       9, 10, 11

Previously Implemented:
=======================
CVE:            References:  Type:  Severity:  Updated AOSP versions:  Prior Change:
CVE-2021-0428   A-173421434  ID     High       10                      bee5bbdc51fe
                                                                       dd80f1e5137f
                                                                       c49a04527460
                                                                       1efc993961
                                                                       5f5f8c7871
                                                                       5fbde70cbb
                                                                       3178770a25
                                                                       9b12a56b0a
                                                                       481350b3

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

Not Applicable (platform source):
=================================
CVE:            References:  Type:  Severity:  Updated AOSP versions:
CVE-2021-0685   A-191055353  EoP    High       11
CVE-2021-0691   A-188554048  EoP    Moderate   11
CVE-2021-0693   A-184046948  ID     High       11

Change-Id: I721aa3f15bdbfbd78de352f77e30f8eab4a79727