Update devcontainer.json

Author: Chuxel

containers/docker-existing-docker-compose/.devcontainer/devcontainer.json

@@ -15,13 +15,13 @@
 
     // "The optional 'workspaceFolder' property is the path VS Code should open by default when"
     // "connected. This is typically a file mount in .devcontainer/docker-compose.yml"
-    "workspaceFolder": "/workspace"
+    "workspaceFolder": "/workspace",
 
     // "Add any extensions you want auto-installed here."
     "extensions": [],
 
     // "Remove this line if you want to keep your containers running after VS Code shuts down."
-    "shutdownAction": "stopCompose",
+    "shutdownAction": "stopCompose"
 
     // "Other notes:"
     // "- The 'appPorts' property is not supported in the Docker Compose case. Add the ports into"