alternative for cleaning untracked directory

Author: anchal20

README.md

@@ -317,5 +317,11 @@ git clean -f
 git clean -f -d
 ```
 
+
+__Alternatives:__
+```sh
+git clean -df
+```
+
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tips.json

@@ -181,6 +181,6 @@
   {
     "title": "Forcefully remove untracked directory",
     "tip": "git clean -f -d",
-    "alternatives": "git clean -df"
+    "alternatives": ["git clean -df"]
   }
 ]