tools: Replace log4j with JUL backend in tests

Replaces log4j with java.util.logging backend in tools tests.

Change-Id: Iea7e88ba482dfa31472286067581adaab5830c8c
Bug-Url: https://bugzilla.redhat.com/1109871
Signed-off-by: Martin Perina <mperina@redhat.com>