impl

  steps:
  - name: ssh
    image: relaysh/ssh-step-exec
    spec:
      connection: !Connection {type: ssh, name: my-ssh-connection}
      username: relay
      port: 2222 # defaults to 22
      knownHosts: |
        server1.example.com ssh-rsa AAAAEXAMPLE
        server2.example.com ssh-rsa AAAANOTHEREXAMPLE
      # or
      #strictHostKeyChecking: false
      on:
      - server1.example.com
      - server2.example.com
      input:
      - whoami
      - uptime
      - cat /etc/passwd

  someImmutableSet = Collections.unmodifiableSet(new HashSet<E>(someSet));