Bump Security String to 2020-06-05

Previously Implemented:
============
CVE:            References:  Type:  Severity:  Updated AOSP versions:
CVE-2019-2219   A-119041698  ID     High       8.0, 8.1, 9, 10
CVE-2020-0113   A-150944913  ID     High       9, 10
CVE-2020-0115   A-150038428  EoP    High       8.0, 8.1, 9, 10
CVE-2020-0117   A-151155194  RCE    Critical   8.0, 8.1, 9, 10
CVE-2020-8597   A-151153886  RCE    Critical   8.0, 8.1, 9, 10

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

Not Applicable (platform source):
===============
CVE:            References:  Type:  Severity:  Updated AOSP versions:
CVE-2019-9460   A-62535446   EoP    High       10
CVE-2020-0114   A-147606347  EoP    High       10
CVE-2020-0116   A-151330809  ID     High       10
CVE-2020-0118   A-150904694  EoP    High       10
CVE-2020-0119   A-150500247  ID     High       10
CVE-2020-0121   A-148180766  ID     High       10

Change-Id: I63a892d513d674b9f60bf121b46bb8b64c4b1c80