Fix link to contributors guide (#2969)

Author: Mathias Monnerville

README.md

@@ -45,7 +45,7 @@ Other documentation details can be found at https://docs.nano.org.
 
 ### Want to Contribute?
 
-Please see the [contributors guide](https://docs.nano.org/protocol-design/overview/#contributing-code-to-the-nano-node).
+Please see the [contributors guide](https://docs.nano.org/node-implementation/contributing/).
 
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