Update docker for tensorboard

Dockerfile

@@ -13,8 +13,6 @@ USER root
 RUN apt-get update && \
   apt-get install -y --no-install-recommends \
   apt-utils \
-  # Display server xvfb needed for Selenium 
-#   xvfb \ 
   # Geckodriver needed for Selenium
   firefox-geckodriver 
 USER ${NB_USER}
@@ -24,4 +22,8 @@ COPY requirements.txt environment.yml /tmp/
 RUN conda env update -q -f /tmp/environment.yml && \
     /opt/conda/bin/pip install -r /tmp/requirements.txt && \
     conda clean -y --all && \
-    conda env export -n "root"
+    conda env export -n "root"
\ No newline at end of file
+    
+# Tensorboard extension
+RUN jupyter labextension install jupyterlab_tensorboard && \
+    pip install jupyter-tensorboard==2.1.1
\ No newline at end of file