Fix broken link to Federation Quickstart (#3150)

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Fixing a broken link to Federation Quickstart. Broken link appears [here
in the
docs](https://www.apollographql.com/docs/federation/building-supergraphs/router/#choosing-a-router-library)

docs/source/building-supergraphs/router.mdx

@@ -26,7 +26,7 @@ Apollo actively supports the following options for your router:
 - **The graphos Router (recommended)**: This is a high-performance, precompiled Rust binary.
 
     - If you're getting started with federation, we recommend [creating a cloud supergraph](/graphos/quickstart/cloud/) with Apollo GraphOS. With a cloud supergraph, GraphOS provisions and manages your router for you.
-    - You can also host your own GraphOS Router instances. [See the Federation Quickstart](../quickstart/setup/) to get started.
+    - You can also host your own GraphOS Router instances. [See the Federation Quickstart](../quickstart/]) to get started.
 
 - **Apollo Server**: Apollo Server can act as your router via the [`@apollo/gateway`](https://www.npmjs.com/package/@apollo/gateway) extension library.
     - [See how to set up Apollo Gateway](/apollo-server/using-federation/apollo-gateway-setup).