[ci] update docker python
@@ -8,7 +8,8 @@ RUN bash install_dependencies_run.sh
RUN curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
RUN python3.8 get-pip.py && rm get-pip.py
RUN update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.8 2
-RUN update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.6 1
+# Comment out this line since Ubuntu 20.04 does not support it
+# RUN update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.6 1
ADD requirements.txt requirements.txt
ENV PYTHON_EXEC=python3.8
RUN ${PYTHON_EXEC} -m pip install -r requirements.txt
