update tests to correspond to the new way to construct d2 graphs

tests/d2_graph_test.py

@@ -10,7 +10,8 @@ from tests.d_graph_data import complete_graph
 
 class TestD2Graph(unittest.TestCase):
     def test_construction(self):
-        d2 = D2Graph(complete_graph, 6)
+        d2 = D2Graph(complete_graph)
+        d2.construct_from_barcodes(index_size=6, verbose=False)
 
         # Evaluate the number of candidate unit d_graphs generated
         for node, candidates in d2.d_graphs_per_node.items():
@@ -38,7 +39,8 @@ class TestD2Graph(unittest.TestCase):
 
 
             G = gm.generate_d_graph_chain(size, d)
-            d2 = D2Graph(G, index_size=index_k)
+            d2 = D2Graph(G)
+            d2.construct_from_barcodes(index_size=index_k, verbose=False)
 
             # Test the number of d-graphs
             awaited_d_num = size - 2 * d