[DEVELOPMENT] Consider implementing an RGCN

[KristinaUlicna]

Details here, preliminary implementation attempt 👇

grace/grace/models/classifier.py

Lines 114 to 124 in b59c4d5

	elif classifier_type == "RGCN":
	self.conv_layer_list = ModuleList(
	[
	RGCNConv(
	in_channels=hidden_channels_list[i],
	out_channels=hidden_channels_list[i + 1],
	num_relations=num_heads,
	)
	for i in range(len(hidden_channels_list) - 1)
	]
	)