Rename package

[cmoulliard]

As the class https://github.com/openshiftio/booster-common/blob/master/openshift-test-utils/src/main/java/io/openshift/booster/test/OpenShiftTestAssistant.java is not specific to booster but serves a more general purpose, we should probably rename it from

package io.openshift.booster.test;

to

package io.openshift.test;