refactore: move layers to be more performant

Author: Sylvain Fraïssé

Dockerfile

@@ -3,8 +3,7 @@ FROM techio/maven3-builder:1.3
 ENV TECHIO_RUN_DIR /project/answer
 
 # Copy files
-COPY target/java-maven3-junit4-runner-0.0.1-SNAPSHOT-jar-with-dependencies.jar /usr/src/codingame/junit-runner/junit-runner.jar
 COPY docker/junit-runner /usr/src/codingame/junit-runner/
+COPY target/java-maven3-junit4-runner-0.0.1-SNAPSHOT-jar-with-dependencies.jar /usr/src/codingame/junit-runner/junit-runner.jar
 
 ENTRYPOINT ["/usr/src/codingame/junit-runner/junit-runner"]
-