fix(build): disable jar creation for authorization server

[fablefebvre]

I just tried to build Chapter11 and faced this issue:

Step 3/12 : ADD ./build/libs/*.jar app.jar
When using ADD with more than one source file, the destination must be a directory and end with a /
ERROR: Service 'auth-server' failed to build : Build failed
➜  Chapter11 git:(main) ✗ ll spring-cloud/authorization-server/build/libs
total 47M
-rw-rw-r-- 1 a506486 a506486 47M Dec 15 15:15 authorization-server-1.0.0-SNAPSHOT.jar
-rw-rw-r-- 1 a506486 a506486 12K Dec 15 15:15 authorization-server-1.0.0-SNAPSHOT-plain.jar
➜  Chapter11 git:(fix/chapter-11) ✗

This PR should fix that.

[magnus-larsson]

Hello and thanks for reporting this issue!

It seems that this issue only happens if you use Docker without BuildKit, but I will of course apply your PR to Chapter 11 and beyond anyhow. The problem disappears if you enable the BuildKit with the command:

DOCKER_BUILDKIT=1 docker compose build auth-server

Note #1: BuildKit is the default builder in Docker engine since v23.0, see https://docs.docker.com/engine/release-notes/23.0/#2300

Note #2: if you want to know more about this difference in the old and new builder in Docker engine, see moby/buildkit#1853