Equalize Dockerfile with other pipelines

Dockerfile

@@ -36,8 +36,6 @@ RUN python2 -m virtualenv "${PYTHON2_VENV_PATH}" \
 ENV PATH="${PYTHON3_VENV_PATH}/bin:${PYTHON2_VENV_PATH}/bin:${PATH}"
 
 
-COPY --chown=generic:generic packages packages
-COPY --chown=generic:generic requirements.txt .
 ENV PYFLOW_VERSION="1.1.20"
 RUN wget \
       --output-document - \
@@ -46,9 +44,13 @@ RUN wget \
  && cd "pyflow-${PYFLOW_VERSION}" \
  && python2 setup.py build install \
  && cd - > /dev/null \
- && rm --recursive "pyflow-${PYFLOW_VERSION}" \
- && python3 -m pip install --upgrade pip \
- && python3 -m pip install -r requirements.txt \
+ && rm --recursive "pyflow-${PYFLOW_VERSION}"
+
+
+COPY --chown=generic:generic packages packages
+COPY --chown=generic:generic requirements.txt .
+RUN python3 -m pip install --upgrade pip \
+ && python3 -m pip install --requirement requirements.txt \
  && rm --recursive packages requirements.txt