Since Murano now requires Glance Artifact Repository to be its package
storage the appropriate UI setting is set by default.
The 'murano_glance_artifacts_plugin' additional component setting is
modified to not be restricted to experimental deployments and its
default value is set to True.
Change-Id: Ieaa373d52403b834aa17eeb05a70b37c61454ad0
Closes-Bug: #1556133