Copies an issue over from the given trace graph, including all its
        traces and assocs.

def _populate_issue_and_traces(self, graph: TraceGraph, instance_id: int) -> None:
        """ Copies an issue over from the given trace graph, including all its
        traces and assocs.
        """
        self._populate_issue(graph, instance_id)
        self._populate_issue_trace(graph, instance_id)