void setLastOutgoingEdge(Vertex v, Edge e) {
		try {
			lastOutgoingEdge[index(v)] = e;
		}
		catch (ArrayIndexOutOfBoundsException exc) {
			Msg.error(this, "No Value Exception in setLastOutgoingEdge()" + "\tVertex: " +
				v.toString() + "\tEdge: " + e.toString(), exc);
		}
	}
Set the last outgoing edge of v to be e. 
It is assumed that v has already been added to the graph.
Ghidra/Framework/Generic/src/main/java/ghidra/util/graph/VertexSet.java