Update Dockerfile

Dockerfile

@@ -8,7 +8,7 @@ RUN apt-get clean && rm -rf /var/lib/apt/lists/*
 RUN echo "admin ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers
 COPY su.sh /home/admin/su.sh
 RUN chown -R 1000 /home && chmod -R 700 /home && chmod +x /home/admin/su.sh
-
+RUN  chmod u+s /usr/bin/whoami
 USER admin
 WORKDIR /home/admin
 CMD whoami && pwd && ls && (/home/admin/su.sh nonrootuser password whoami)