Misconfigured nodes lead to "loops not allowed"

[sebastian-peter]

If the two nodes that a (2w) transformer connects have the same subnet number, ContainerUtils crashes with:

java.lang.IllegalArgumentException: loops not allowed
	at org.jgrapht.graph.AbstractBaseGraph.addEdge(AbstractBaseGraph.java:277)
	at edu.ie3.datamodel.utils.ContainerUtils.buildSubGridTopologyGraph(ContainerUtils.java:582)
	at edu.ie3.datamodel.utils.ContainerUtils.buildSubGridTopologyGraph(ContainerUtils.java:515)
	at edu.ie3.datamodel.models.input.container.JointGridContainer.<init>(JointGridContainer.java:32)
	at edu.ie3.datamodel.io.source.csv.CsvJointGridContainerSource.read(CsvJointGridContainerSource.java:101)
	at edu.ie3.simona.io.grid.GridProvider$.gridFromConfig(GridProvider.scala:48)
	at edu.ie3.simona.sim.setup.SimonaStandaloneSetup.gridAgents(SimonaStandaloneSetup.scala:74)
	at edu.ie3.simona.sim.SimonaSim$$anonfun$edu$ie3$simona$sim$SimonaSim$$initializing$1.applyOrElse(SimonaSim.scala:114)

This is very much not helpful. So it'd be great to check for this condition beforehand and throw an exception that includes information about the error that occurred, including transformer and nodes.
One should also check for the same thing with 3w transformers.