[11u] RFR(XS) 8239792: Bump update version for OpenJDK: jdk-11.0.8

[Lindenmaier, Goetz]

Hi,

to start development of jdk-11.0.8, we need to bump
the version:
http://cr.openjdk.java.net/~goetz/wr20/8239792-version_11.0.8-jdk11/01/

Please review.

Naturally, I will only push this after dev close of 11.0.7,
and after JBS was updated to tag for 11.0.8.

For the date, see also https://www.oracle.com/security-alerts/

Thanks,
  Goetz.