Try enabling nbextensions_configurator explicitly

May allow us to switch to jupyter server here too. I had
to remove the nbclassic-serverextension install line from
here: Jupyter-contrib/jupyter_nbextensions_configurator#153

Dockerfile

@@ -31,4 +31,8 @@ RUN mamba env update -p ${CONDA_DIR} -f /tmp/environment.yml && mamba clean -afy
 # So we download alongside our packages.
 # Note that textblob.download_corpora just calls nltk to download corpora
 ENV NLTK_DATA ${CONDA_DIR}/nltk_data
-RUN mkdir -p ${NLTK_DATA} && python -m textblob.download_corpora
+RUN mkdir -p ${NLTK_DATA} && python -m textblob.download_corpora
+
+RUN jupyter nbclassic-extension install --sys-prefix --py jupyter_nbextensions_configurator --overwrite && \
+    jupyter nbclassic-extension enable --sys-prefix --py jupyter_nbextensions_configurator && \
+    jupyter nbclassic-serverextension enable --sys-prefix --py jupyter_nbextensions_configurator