fix building process

Dockerfile

@@ -16,7 +16,7 @@ RUN apk add --no-cache --update ca-certificates wget \
 COPY docker/runner/config/application.tmpl /config/application.tmpl
 COPY docker/runner/README.md docker/runner/run.sh /
 
-COPY target/portal-backend-$VERSION.jar backend.jar
+COPY target/portal-backend.jar backend.jar
 
 EXPOSE 8080
 

pom.xml

@@ -242,6 +242,7 @@
     </pluginRepositories>
 
     <build>
+        <finalName>portal-backend</finalName>
         <resources>
             <resource>
                 <directory>src/main/resources</directory>