Update Java buildpack

This change updates the Java buildpack to its latest commit.  This
brings in changes to the version of the Auto-reconfiguration JAR and
Play JPA plugin in order connect with ElephantDB.

[#53775581]
Merge branch '53775581-update-java-buildpack' of git://github.com/nebhale/dea_ng into nebhale-53775581-update-java-buildpack