Quickstarts should be updated to use the resteasy-jackson2-provider

JBoss EAP 6 used the `resteasy-jackson-provider`.
JBoss EAP 7 uses the `resteasy-jackson2-provider` by default

The quickstarts should use the version provided with JBoss EAP 7.

This affects the following quickstarts:

jaxrs-client
managed-executor-service
tasks-rs

See the related doc issue here:https://issues.jboss.org/browse/JBEAP-2307?focusedCommentId=13144852&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13144852