java/openjdk8: unbreak TEST=on after 4dca33c0a4a3

$ make checksum WITH=TEST

> License GPLv2 accepted by the user

> openjdk8-8.302.08.1 depends on file: /usr/local/sbin/pkg - found

> Fetching all distfiles required by openjdk8-8.302.08.1 for building

> No SHA256 checksum recorded for jtreg4.1-b08.tar.gz.

> No suitable checksum found for jtreg4.1-b08.tar.gz.

> SHA256 Checksum OK for battleblow-jdk8u-8.302.08.1-jdk8u302-b08.1_GH0.tar.gz.

• Error code 1

Reported by: Philipp Ost (via ports@ list)