apk upgrade is unnecessary in Dockerfile

Author: martijnrondeel

Dockerfile

@@ -6,7 +6,7 @@ FROM node:alpine
 LABEL maintainer="[email protected]"
 EXPOSE 3030
 
-RUN apk update && apk upgrade && apk add --no-cache python2 curl
+RUN apk update && apk add --no-cache python2 curl
 
 COPY --from=py-ea /usr/lib/python2.7/site-packages /usr/lib/python2.7/site-packages
 COPY --from=py-ea /opt/elastalert /opt/elastalert