Fixing CApp deployment issue

Hi,
Currently when deploying a CApp with WSO2 ESB, artifacts state finally become "Pending". Because of that process of undeploying artifacts fails.
Reason for that was figured out as engaging Default Artifact Deployer after Synapse App Deployer. This patch is to fix it.
JIRA link: https://wso2.org/jira/browse/CARBON-14906

Thanks!