Change pip3 to python3 -m pip in Dockerfile

Author: okofish

Dockerfile

@@ -4,7 +4,7 @@ USER root
 
 RUN apt-get update -y && \
   apt-get install -y python3 python3-pip && \
-  pip3 install wolframclient
+  python3 -m pip install wolframclient
 
 COPY . /tmp/build
 RUN pip3 install /tmp/build && \