RFR: JDK-8203497: Bump Jib format version to 1.2

[Tim Bell]

Erik:

> The jib format version is defined in jib-profiles.js. It is used by Jib
> to identify correct parsing of the file and adjust behavior of Jib if
> necessary. This version needs to be bumped to 1.2.
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8203497
>
> Webrev: http://cr.openjdk.java.net/~erikj/8203497/webrev.01/

Looks good.

Tim