OpenShift: We can't provide Java arguments

After having fixed this ticket https://issues.redhat.com/browse/QUARKUS-866, we could add Java arguments via the jvmArgs properties (which was wrong and fixed as part of this PR). However, now we don't have any properties or way to add real Java arguments.

As an example, the args section in the YAML look like:

args:
    - '-Dquarkus.http.host=0.0.0.0'
    - '-Djava.util.logging.manager=org.jboss.logmanager.LogManager'
    - '-jar'
    - /deployments/quarkus-run.jar

And what we can't achieve is to add Java arguments:

args:
    - '-Dquarkus.http.host=0.0.0.0'
    - '-Djava.util.logging.manager=org.jboss.logmanager.LogManager'
    - '-jar'
    - /deployments/quarkus-run.jar
    - ARG1
    - ARG2

I tried to use the property `quarkus.openshift.arguments` but it's replacing all the args section as:

args:
    - ARG1
    - ARG2

I think this issue is also relevant for Kubernetes and S2I.