parameterize ACS version in Dockerfile

alfresco-content-repository/docker/Dockerfile

@@ -1,3 +1,4 @@
+ARG ACS_TAG=inject-it
 FROM alfresco/alfresco-content-repository-community:${ACS_TAG}
 
 ARG USERNAME=alfresco

docker-compose.yml

@@ -4,7 +4,10 @@ version: "3"
 
 services:
     platform:
-        build: ./alfresco-content-repository/docker
+        build:
+            context: ./alfresco-content-repository/docker
+            args:
+                ACS_TAG: ${ACS_TAG}
         image: local/alfresco-content-repository:latest
         environment:
             JAVA_TOOL_OPTIONS: "