Update Dockerfile

Dockerfile

@@ -38,6 +38,7 @@ ENV POSTGRES_USER=${POSTGRES_USER} \
     WEBDAV_URL=${WEBDAV_URL} \
     WEBDAV_USER=${WEBDAV_USER} \
     WEBDAV_PASSWORD=${WEBDAV_PASSWORD} \
+    WORKDIR=${WORKDIR} \
     PATH="$WORKDIR/venv/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:$PATH"
 
 COPY requirements.txt ${WORKDIR}/requirements.txt