Add correct README example

Containerfile.www

@@ -21,7 +21,7 @@ ARG CONSUMER_SECRET
 ARG OAUTH_TOKEN
 ARG OAUTH_SECRET
 ARG BLOG_NAME
-ENV TBS_TS="1999-09-09 09:09"
+ENV TBS_LAST_SYNC="1999-09-09 09:09"
 ENV TBS_CONSUMER_KEY "$CONSUMER_KEY"
 ENV TBS_CONSUMER_SECRET "$CONSUMER_SECRET"
 ENV TBS_OAUTH_TOKEN "$OAUTH_TOKEN"
@@ -30,7 +30,7 @@ ENV TBS_BLOG_NAME "$BLOG_NAME"
 
 FROM env AS final
 RUN mkdir /app/site /app/src/posts
-RUN python backup.py $TBS_BLOG_NAME
+RUN python backup.py
 RUN (cd src && nikola build)
 
 FROM docker.io/nginx:alpine AS www

README

@@ -51,7 +51,7 @@ podman build \
 --build-arg OAUTH_SECRET=<replace me> \
 --build-arg OAUTH_TOKEN=<replace me> \
 --build-arg BLOG_NAME=<replace me> \
-.
+-f Containerfile.www
 
 podman run -p 8080:80 <container image id>