Update README.md

that extra period was creating confusion and I was adding two periods which was throwing an error.

examples/with-docker/README.md

@@ -17,7 +17,7 @@ pnpm create next-app --example with-docker nextjs-docker
 ## Using Docker
 
 1. [Install Docker](https://docs.docker.com/get-docker/) on your machine.
-1. Build your container: `docker build -t nextjs-docker .`.
+1. Build your container: `docker build -t nextjs-docker .`
 1. Run your container: `docker run -p 3000:3000 nextjs-docker`.
 
 You can view your images created with `docker images`.