core: ActionGroupDAOTest#testRemoveActionVersionMap

The current implementation of this test removes existingActionMap from
the database. Since there is no rollback performed between tests, and
since other tests in this class assume this object will be present in
the database, this implementation caused sporadic failures on various
environments [1], depending on the order the tests were executed.

This patch rewrites the test to be safer. It now creates a dummy record
in the table, inserts it (and asserts it was indeed inserted), and then
removes it (again, asserting it was properly removed).

[1] Details of the system where a failure was spotted:
Apache Maven 3.0.4 (r1232337; 2012-01-17 10:44:56+0200)
Maven home: /usr/local/apache-maven-3.0.4
Java version: 1.7.0_51, vendor: Oracle Corporation
Java home: /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.51.x86_64/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "2.6.32-431.11.2.el6.x86_64", arch: "amd64", family: "unix"

Change-Id: Icba824009bec7763c38b3040eb9b1be88558f037
Signed-off-by: Allon Mureinik <amureini@redhat.com>