Add nano and tree commands

Dockerfile

@@ -1,6 +1,6 @@
 FROM ubuntu
 
-RUN apt update && apt install openssh-server sudo -y
+RUN apt update && apt install tree nano openssh-server sudo -y
 RUN useradd -rm -d /home/ubuntu -s /bin/bash -g root -G sudo -u 1000 test 
 RUN  echo 'test:test' | chpasswd
 RUN service ssh start