[docs] Changed format for class diagrams

docs/diagrams/class_diagram.py

@@ -9,7 +9,7 @@ from pyUML import Graph, UMLClass
 def print_and_save(graph, name):
     #print(graph.to_string())
     #graph.write_raw(f"{name}.dot")
-    graph.write(f"{name}.png")#, "dot", "png")
+    graph.write(f"{name}.png", "dot", "png")
 
 def generate_input_uml():
     # Create UML for the input classes