Update quick-start.md

quick-start.md, had error in the links provided at last. They are missing file extension ( .md ) that leads to 404 page not found

docs/node-guide/quick-start.md

@@ -43,8 +43,8 @@ gaianet stop
 
 ## Next steps
 
-* [Customize](customize) your node. You probably do not wish to just run the default Phi-3 model and Paris knowledge base. 
-* [Register](register) and join the GaiaNet protocol network to receive payments.
-* [Protect](tasks/protect) the node server to ensure stable service.
-* Install and manage [multiple nodes](tasks/multiple) on a single machine.
+* [Customize](customize.md) your node. You probably do not wish to just run the default Phi-3 model and Paris knowledge base. 
+* [Register](register.md) and join the GaiaNet protocol network to receive payments.
+* [Protect](tasks/protect.md) the node server to ensure stable service.
+* Install and manage [multiple nodes](tasks/multiple.md) on a single machine.