Update docs links

- remove stack docs
- change link from community to docs.optimism.io

README.md

@@ -15,8 +15,7 @@ In this repository, you'll find numerous core components of the OP Stack, the de
 
 ## Documentation
 
-- If you want to build on top of OP Mainnet, refer to the [Optimism Community Hub](https://community.optimism.io)
-- If you want to build your own OP Stack based blockchain, refer to the [OP Stack docs](https://stack.optimism.io)
+- If you want to build on top of OP Mainnet or build your own OP Stack based blockchain, refer to the [Optimism Documentation](https://docs.optimism.io)
 - If you want to contribute to the OP Stack, check out the [Protocol Specs](./specs)
 
 ## Community