FIX: show only selected rules in DOT rendering

[redeboer]

Previously, a DOT rendering of a ProblemSet rendered only rule_priorities. This is, however, just an exhaustive list of priorities for each rule that are in most cases the default rule prioties, not a list of selected rules for each node or edge. This fix renders the selected conservation_rules instead:

Code snippet

import graphviz

import qrules
from qrules.settings import InteractionType
from qrules.transition import StateTransitionManager

stm = StateTransitionManager(
    initial_state=["Lambda(c)+"],
    final_state=["p", "K-", "pi+"],
    mass_conservation_factor=0.6,
)
stm.set_allowed_interaction_types([InteractionType.WEAK], node_id=0)
stm.set_allowed_interaction_types([InteractionType.STRONG], node_id=1)
problem_sets = stm.create_problem_sets()
problem_set, *_ = problem_sets.values()
src = qrules.io.asdot(problem_set[0], render_node=True)
graphviz.Source(src)

Before

After