Change the logic when you want a cluster with only 3 nodes (all doing anything)

[jmaitrehenry]

If we want to build a cluster with only 3 nodes that do all roles (master, ingest and receive request) we should:

• Update the data node to have master to true
• The LB should point on them

When we want to add a dedicated cluster of master, the data node should become master: false and the LB should continue point on master node.

Actually the LB will point on the master nodes VMSS with the data: true config.

We can't move with terraform a lb backend pool from one VSS to another one.