add link to rfc-0001 in broker README (#1862)

# Description
- What does this PR do?
  - link added
- Why are these changes needed?
  - improve docs
- How were these changes implemented and what do they affect?
  - only concerns docs

docs/DOCUMENTATION_GUIDELINES.md

@@ -210,7 +210,7 @@ The guidelines so far have been general in nature, and are applicable to crates
 pallets.
 
 The following is relevant to how to document parts of a crate that is a pallet. See
-[`pallet-fast-unstake`](../frame/fast-unstake/src/lib.rs) as one example of adhering these guidelines.
+[`pallet-fast-unstake`](../substrate/frame/fast-unstake/src/lib.rs) as one example of adhering these guidelines.
 
 ---
 

substrate/frame/broker/README.md

@@ -2,7 +2,7 @@
 
 Brokerage tool for managing Polkadot Core scheduling.
 
-Properly described in RFC-0001 Agile Coretime.
+Properly described in [RFC-0001 Agile Coretime](https://github.com/polkadot-fellows/RFCs/blob/main/text/0001-agile-coretime.md).
 
 ## Implementation Specifics