consider renaming apstra_datacenter_blueprint_system_node -> apstra_datacenter_system

[chrismarget-j]

Data source apstra_datacenter_blueprint_system_nodes returns a list of graph node IDs of system nodes.
Data source apstra_datacenter_blueprint_system_node returns detailed info about a single system node.

We'll likely be creating a bunch of data sources that follow this pattern. Currently in queue are data sources for routing_zones/routing_zone and virtual_networks/virtual_network.

Are the words blueprint and node really helping much here?

Should they instead be:

• apstra_datacenter_systems
• apstra_datacenter_system
• apstra_datacenter_routing_zones
• apstra_datacenter_routing_zone
• apstra_datacenter_virtual_networks
• apstra_datacenter_virtual_network

[rajagopalans]

My vote is for apstra_datacenter_* apstra_datacenter_blueprint* seems a little extra

[chrismarget-j]

When I first created the system/systems data source it was a big departure from the others: Totally graph-query based.

This felt like a big departure...

But it's really only relevant to me as the implementer. I don't think the end user needs to know this level of detail.

[chrismarget-j]

Fixed by #104. Thank you @bwJuniper!