Update Dockerfile (microsoft#3298)

line 98 should be
curl -O https://bootstrap.pypa.io/pip/3.6/get-pip.py && \
to avoid
microsoft#16 106.9 ERROR: This script does not work on Python 3.6 The minimum supported Python version is 3.7. Please use https://bootstrap.pypa.io/pip/3.6/get-pip.py instead.

Co-authored-by: Logan Adams <114770087+loadams@users.noreply.github.com>

docker/Dockerfile

@@ -95,7 +95,7 @@ ENV PYTHON_VERSION=3
 RUN apt-get install -y python3 python3-dev && \
         rm -f /usr/bin/python && \
         ln -s /usr/bin/python3 /usr/bin/python && \
-        curl -O https://bootstrap.pypa.io/get-pip.py && \
+        curl -O https://bootstrap.pypa.io/pip/3.6/get-pip.py && \
         python get-pip.py && \
         rm get-pip.py && \
         pip install --upgrade pip && \