private boolean groupContainsEntry(GroupedFunctionGraphVertex vertex) {
		Set<FGVertex> groupVertices = vertex.getVertices();
		for (FGVertex groupedVertex : groupVertices) {
			FGVertexType vertexType = groupedVertex.getVertexType();
			if (vertex.isEntry()) {
				return true;
			}
			else if (vertexType == FGVertexType.GROUP) {
				return groupContainsEntry((GroupedFunctionGraphVertex) groupedVertex);
			}
		}
		return false;
	}
Any time a vertex is grouped we want to make sure that any previous group affiliations
are removed.

@param groupVertices the new grouping of vertices
Ghidra/Features/FunctionGraph/src/main/java/ghidra/app/plugin/core/functiongraph/graph/FunctionGraph.java