Change instruction order so entrypoint modif is time effective

In terms of docker build for swh-scheduler app.

Refs. sysadm-environment#5035

apps/swh-scheduler/Dockerfile

@@ -13,16 +13,17 @@ USER swh
 WORKDIR /opt/swh
 
 COPY --chown=swh:swh requirements-frozen.txt /opt/swh
-COPY --chown=swh:swh entrypoint.sh /opt/swh
 
 ENV PYTHONPATH=/opt/swh
 ENV PATH=/opt/swh/.local/bin:$PATH
 
-RUN chmod u+x /opt/swh/entrypoint.sh && \
-    /usr/local/bin/python -m pip install --upgrade pip && \
+RUN /usr/local/bin/python -m pip install --upgrade pip && \
     pip install --no-cache-dir -r requirements-frozen.txt && \
     pip install gunicorn
 
+COPY --chown=swh:swh entrypoint.sh /opt/swh
+RUN chmod u+x /opt/swh/entrypoint.sh
+
 ENV SWH_CONFIG_FILENAME=/etc/swh/config.yml
 ENV PORT 5008
 EXPOSE $PORT