Child scope of container is not visualized on dot graph

[greeflas]

Describe the bug
Child scope of container is not visualized on dot graph.

To Reproduce

1. Create container:
   c := dig.New()
2. Provide the container with constructor:
   c.Provide(NewFirstComponent)
3. Create child scope:
   child := c.Scope("test_scope")
4. Provide the child scope with constructor:
   child.Provide(NewSecondComponent)
5. Visualize container:
   dig.Visualize(c, os.Stdout)

Expected behavior
I expect to see child scope along with NewSecondComponent but I only see NewFirstComponent.

Additional context
Dig version: v1.17.1
Go Playground: https://go.dev/play/p/lhYAIUlfsPr
DOT:

digraph {
	rankdir=RL;
	graph [compound=true];
	
		subgraph cluster_0 {
			label = "main";
			constructor_0 [shape=plaintext label="NewFirstComponent"];
			
			"*main.FirstComponent" [label=<*main.FirstComponent>];
			
		}
		
		
	
}

Graph image:

[sywhang]

This is a valid feature request. I believe the DOT representation wasn't rewritten when we rewrote Dig's internal graph representation when we worked on the Scope feature.

[greeflas]

@sywhang should we close this issue or you want to add here info about future improvement that was discussed in pull request?

[sywhang]

I'll leave this open for now since we need some more visual improvements. Thanks