Add missing runtime deps

Dockerfile

@@ -21,7 +21,7 @@ COPY --from=staging /build /usr
 ENV PYTHONPATH=/usr/lib/python3.5/site-packages
 
 # Add runtime system deps
-RUN apk add --update --no-cache wget gzip libmagic git unzip libpq
+RUN apk add --update --no-cache wget gzip libmagic git unzip libpq libxslt libjpeg
 
 # Add unprivilegied user
 RUN addgroup -g 1000 teklia && adduser -D -u 1000 -G teklia ark