Use npm install --include=dev instead of --dev

to resolve an npm warning

Author: atodorov

Dockerfile.buildroot

@@ -31,7 +31,7 @@ RUN pip3 install --no-cache-dir -r requirements/mariadb.txt -r requirements/post
 RUN sed -i "s/tcms.settings.devel/tcms.settings.product/" manage.py
 
 # compile tcms/static/js/bundle.js explicitly
-RUN pushd tcms/ && npm install --dev && ./node_modules/.bin/webpack && popd
+RUN pushd tcms/ && npm install --include=dev && ./node_modules/.bin/webpack && popd
 
 RUN ./tests/check-build
 RUN pip3 install --no-cache-dir dist/kiwitcms-*.tar.gz