compress edge if it crosses a traffic signal

[wangyoucao577]

I saw below comments and codes at graph_compressor.cpp#L210:

    /*
    // Do not compress edge if it crosses a traffic signal.
    // This can't be done in CanCombineWith, becase we only store the
    // traffic signals in the `traffic signal` list, which EdgeData
    // doesn't have access to.
    */
    const bool has_node_penalty = traffic_signals.find(node_v) != traffic_signals.end();
    EdgeDuration node_duration_penalty = MAXIMAL_EDGE_DURATION;
    EdgeWeight node_weight_penalty = INVALID_EDGE_WEIGHT;
    if (has_node_penalty)
    {
        ...
    }

From above codes, I think the "compress edge if it crosses a traffic signal" has already been implemented. But the comments make me confused when I'm reading these codes.
After check the commit history, I found that the function has been merged by PR #4327 , only comments not up to date.

[wangyoucao577]

I have created PR #5384 for correct the comments here.