Cleanup Docker clean steps

itdominator-gui-base-image/Dockerfile

@@ -92,12 +92,11 @@ RUN npm --version
 # 4. ...
 
 # 5. Cleanup
-RUN apt-get autoremove -y --purge
-RUN apt-get autoclean
-
-RUN rm -rf /var/lib/apt/lists/*
-RUN rm -rf /tmp/*
-RUN rm requirements.txt
+RUN apt-get autoremove -yqq --purge \
+  && apt-get clean \
+  && rm -rf /var/lib/apt/lists/* \
+  && rm -rf /tmp/*
+  && rm requirements.txt
 
 # 6. Expose Port and define the command used to run the app
 CMD ["bash"]