Remove not needed line

Author: josecoelho96

deployment/nginx/Dockerfile

@@ -2,8 +2,7 @@ FROM nginx:1.15.2-alpine
 ARG SERVER_NAME
 
 COPY ./config/nginx/nginx.conf /etc/nginx/
-COPY ./config/nginx/slackbot.conf /slackbot.conf
-RUN envsubst '${SERVER_NAME}' < /slackbot.conf > /etc/nginx/conf.d/slackbot.conf && rm /slackbot.conf
+COPY ./config/nginx/slackbot.conf /etc/nginx/conf.d/slackbot.conf
 RUN rm /etc/nginx/conf.d/default.conf
 
 COPY ./config/nginx/ssl/cert.pem /etc/nginx/ssl/cert.pem