Bump Security String to 2020-07-05

Implemented:
============
CVE:            References:     Type:   Severity:       Updated AOSP versions:
CVE-2020-9589   A-156261521     RCE     Critical        8.0, 8.1, 9, 10
CVE-2020-0224   A-147664838     RCE     Critical        8.0, 8.1, 9, 10

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

Not Applicable (platform source):
=================================
CVE:            References:     Type:   Severity:       Updated AOSP versions:
CVE-2020-0227   A-129476618     EoP     High            8.0, 8.1, 9, 10
CVE-2020-0226   A-150226994     EoP     High            10
CVE-2020-0225   A-142546668     RCE     Critical        10
CVE-2020-0122   A-147247775     EoP     High            8.0, 8.1, 9, 10
CVE-2020-0107   A-146570216     ID      High            10

Change-Id: I30f51b17135ce444ec5298788b371fde93fd4ed2