getServer = (servers, serverName) => {
  if (!servers) {
    throw new Error('Provided AsyncAPI document doesn\'t contain Servers object.');
  }
  if (!serverName) {
    throw new Error('Server name must be provided.');
  }
  if (!servers.has(serverName)) {
    throw new Error(`Server "${serverName}" not found in AsyncAPI document. Available servers: ${Array.from(servers.keys()).join(', ')}`);
  }
  return servers.get(serverName);
}
Retrieve a server object from the provided AsyncAPI servers collection.

@param {Map<string, object>} servers - A map of server names to AsyncAPI server objects.
@param {string} serverName - The name of the server to retrieve.

@throws {Error} If any of the parameter is missing or invalid.

@returns {object} The AsyncAPI server object corresponding to the given server name.