Add a new AutomationCoreFeature test feature

In the context of NXP-28474, we want to clean some modules dependencies to avoid cyclic dependencies.

Some modules relies on nuxeo-automation-test only for the AutomationFeature while they only need nuxeo-automation-core.
The current AutomationFeatures deploys too many dependencies for those use cases, add a new one AutomationCoreFeature in nuxeo-automation-core that will be in charge of deploying only Automation Core (and required dependencies).

Modules to update:

• nuxeo-thumbnail
• nuxeo-imaging-core
• nuxeo-platform-rendition-core