stop removing qt

it makes the conda env invalid, which causes errors in later installs

Makefile

@@ -87,4 +87,4 @@ test/%: ## run tests against a stack
 	@TEST_IMAGE="$(OWNER)/$(notdir $@)" pytest test
 
 test/base-notebook: ## test supported options in the base notebook
-	@TEST_IMAGE="$(OWNER)/$(notdir $@)" pytest test base-notebook/test
\ No newline at end of file
+	@TEST_IMAGE="$(OWNER)/$(notdir $@)" pytest test base-notebook/test

scipy-notebook/Dockerfile

@@ -15,8 +15,6 @@ RUN apt-get update && \
 USER $NB_UID
 
 # Install Python 3 packages
-# Remove pyqt and qt pulled in for matplotlib since we're only ever going to
-# use notebook-friendly backends in these images
 RUN conda install --quiet --yes \
     'conda-forge::blas=*=openblas' \
     'ipywidgets=7.4*' \
@@ -43,7 +41,6 @@ RUN conda install --quiet --yes \
     'beautifulsoup4=4.7.*' \
     'protobuf=3.7.*' \
     'xlrd'  && \
-    conda remove --quiet --yes --force qt pyqt && \
     conda clean --all -f -y && \
     # Activate ipywidgets extension in the environment that runs the notebook server
     jupyter nbextension enable --py widgetsnbextension --sys-prefix && \