public MockPeerDiscoveryAgent startDiscoveryAgent(final AgentBuilder agentBuilder) {
    final MockPeerDiscoveryAgent agent = createDiscoveryAgent(agentBuilder);
    agent.start(nextAvailablePort.incrementAndGet()).join();
    return agent;
  }
Start a single discovery agent with the provided bootstrap peers.

@param bootstrapPeers the list of bootstrap peers
@param peerPermissions peer permissions
@return a list of discovery agents.
ethereum/p2p/src/test/java/org/hyperledger/besu/ethereum/p2p/discovery/PeerDiscoveryTestHelper.java