SW-612: Build DAL 3.3.1 and force it to use Python3 during its build

Docker/lofar-base/Dockerfile.tmpl

@@ -127,8 +127,8 @@ apt-get autoremove -y --purge
 #
 RUN apt-get update && apt-get install -y git cmake g++ swig3.0 python3-dev libhdf5-dev && \
     mkdir ${INSTALLDIR}/DAL && \
-    cd ${INSTALLDIR}/DAL && git clone https://github.com/nextgen-astrodata/DAL.git src && cd src && git checkout v3.3.0 && cd .. && \
-    mkdir ${INSTALLDIR}/DAL/build && cd ${INSTALLDIR}/DAL/build && cmake -DCMAKE_INSTALL_PREFIX=${INSTALLDIR}/DAL ../src && \
+    cd ${INSTALLDIR}/DAL && git clone https://github.com/nextgen-astrodata/DAL.git src && cd src && git checkout v3.3.1 && cd .. && \
+    mkdir ${INSTALLDIR}/DAL/build && cd ${INSTALLDIR}/DAL/build && cmake -DPYTHON_INCLUDE_DIR=/usr/include/python${PYTHON_VERSION} -DPYTHON_LIBRARY=/usr/lib/x86_64-linux-gnu/libpython${PYTHON_VERSION}m.so -DCMAKE_INSTALL_PREFIX=${INSTALLDIR}/DAL ../src && \
     make -j ${J} && \
     make install && \
     bash -c "find ${INSTALLDIR}/DAL/lib -name '*.so' | xargs strip || true" && \