Update .gitignore (#3197)

* Remove duplicate 'node_modules'
* Replace 'public/packs'

.gitignore

@@ -19,6 +19,7 @@
 coverage
 public/system
 public/assets
+public/packs
 .env
 .env.production
 node_modules/
@@ -43,9 +44,6 @@ redis
 # Ignore vim files
 *~
 *.swp
-/public/packs
-/node_modules
-
 
 # Ignore npm debug log
 npm-debug.log