chore(CI):update pom path

Author: Thibaut-Mouton

backend/gateway/Dockerfile

@@ -1,11 +1,12 @@
 FROM maven:3.9-amazoncorretto-8-alpine as build
 COPY . .
-RUN mvn package -f backend/gateway/pom.xml
+# At this level, we already are in backend/gateway
+RUN mvn package
 
 FROM amazoncorretto:17.0.17-al2023-headless
 
 LABEL maintainer="Thibaut MOUTON <thibautmouton22@gmail.com>"
 
-COPY --from=build /backend/gateway/targets/*.jar flm.jar
+COPY --from=build targets/*.jar flm.jar
 
 ENTRYPOINT ["java","-jar","/flm.jar"]