pom.xml: update mariadb-java-client to 1.7.2
pom.xml: update mariadb-java-client to 1.7.2

Note that CONJ-490 has been fixed, so connectTimeout is now correctly
interpreted as seconds:

  https://github.com/MariaDB/mariadb-connector-j/commit/c8c1c542c7b4a787553c27c9ec47002f54df2763

Signed-off-by: Pierre-Alexandre Meyer <ff019a5748a52b5641624af88a54a2f0e46a9fb5@mouraf.org>

killbill/killbill-oss-parent