Dockerfile: remove "deploybase" stage, and inline instead

The "deploybase" stage was only used for the final stage.

This patch inlines the steps from that stage to the final stage
itself. In the process, changing the order of copying the NGINX
configuration file to _after_ the docs were copied. This prevents
having to copy the archived docs when making a change in the NGINX
configuration. The NGINX configuration file _will_ now be copied
on each rebuild, but the file is small, and as such is still faster
than copying all archives.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Dockerfile

@@ -39,15 +39,6 @@ ARG DISTRIBUTION_BRANCH
 ENV DISTRIBUTION_BRANCH=${DISTRIBUTION_BRANCH}
 
 
-# Base stage to be used for deploying the docs
-FROM nginx:alpine AS deploybase
-ENV TARGET=/usr/share/nginx/html
-COPY _deploy/nginx/default.conf /etc/nginx/conf.d/default.conf
-
-# Set the default command to serve the static HTML site
-CMD echo -e "Docker docs are viewable at:\nhttp://0.0.0.0:4000"; exec nginx -g 'daemon off;'
-
-
 # Empty stage if archives are disabled (ENABLE_ARCHIVES=false)
 FROM scratch AS archives-false
 
@@ -108,8 +99,13 @@ COPY --from=current /usr/share/nginx/html /
 #
 # To build without archives:
 # DOCKER_BUILDKIT=1 docker build -t docs --build-arg ENABLE_ARCHIVES=false .
-FROM deploybase AS deploy
+FROM nginx:alpine AS deploy
+ENV TARGET=/usr/share/nginx/html
 WORKDIR $TARGET
 
 COPY --from=archives / .
 COPY --from=current  /usr/share/nginx/html .
+
+# Configure NGINX
+COPY _deploy/nginx/default.conf /etc/nginx/conf.d/default.conf
+CMD echo -e "Docker docs are viewable at:\nhttp://0.0.0.0:4000"; exec nginx -g 'daemon off;'