OpenJDK version strings

OpenJDK versions are controlled by is_upstream_release variable in debian/rules

is_upstream_release=yes - upstream release, e.g. 25.0.2+10-1~24.04.1. <Upstream Version>+<build>-<debian-revision>~<backport version>. is_upstream_release= - development preview, e.g. 25~36ea-1. <Upstream Version>~<version>ea-<debian-revision>.

The build fails if the version string in debian/changelog does not match the expected format.