public AgentBuilder bindPort(final int bindPort) {
      if (bindPort == 0) {
        // Zero means pick the next available port
        this.bindPort = OptionalInt.empty();
        return this;
      }
      this.bindPort = OptionalInt.of(bindPort);
      return this;
    }
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