static getNeighbours(ringConnections, ringId) {
    let neighbours = [];

    for (let i = 0; i < ringConnections.length; i++) {
      let ringConnection = ringConnections[i];

      if (ringConnection.firstRingId === ringId) {
        neighbours.push(ringConnection.secondRingId);
      } else if (ringConnection.secondRingId === ringId) {
        neighbours.push(ringConnection.firstRingId);
      }
    }

    return neighbours;
  }
Retruns the neighbouring rings of a given ring.

@static
@param {RingConnection[]} ringConnections An array of ring connections containing ring connections associated with the current molecule.
@param {Number} ringId A ring id.
@returns {Number[]} An array of ring ids of neighbouring rings.