AM fails during embedded replication setup when adding a new node to existing deployment

Bug description

When one attempts to set up an AM environment with multiple AM nodes using the embedded configuration store, the setup of the second AM instance fails.

How to reproduce the issue

• Set up first AM instance using embedded
• Try to add second AM instance to existing deployment

Expected behaviour

Setup successfully completes

Current behaviour

Setup fails to establish replication between the embedded instances

Code analysis

The suggestion from the DS team was that the DS nodes need to share the same deployment key in order to be able to replicate with each other. This means that the first AM node's deployment key needs to be saved somewhere, and most likely we'll need to update getServerInfo.jsp to make it available for the second AM instance.

Alternatively the embedded DS's deployment key could be a secret that needs to be made available before installation.