docs: fix broken links in docs/crates/network.md (paradigmxyz#13948)

docs/crates/network.md

@@ -8,8 +8,6 @@ Reth's P2P networking consists primarily of 4 ongoing tasks:
 - **ETH Requests**: Responds to incoming requests for headers and bodies
 - **Network Management**: Handles incoming & outgoing connections with peers, and routes requests between peers and the other tasks
 
-We'll leave most of the discussion of the discovery task for the [discv4](./discv4.md) chapter, and will focus on the other three here.
-
 Let's take a look at how the main Reth CLI (i.e., a default-configured full node) makes use of the P2P layer to explore the primary interfaces and entrypoints into the `network` crate.
 
 ---
@@ -168,8 +166,6 @@ The `Swarm` struct glues together incoming connections from peers, managing sess
 
 We'll touch more on the `NetworkManager` shortly! It's perhaps the most important struct in this crate.
 
-More information about the discovery task can be found in the [discv4](./discv4.md) chapter.
-
 The ETH requests and transactions task will be explained in their own sections, following this one.
 
 The variable `network` returned from `start_network` and the variable `fetch_client` returned from `network.fetch_client` are of types `NetworkHandle` and `FetchClient`, respectively. These are the two main interfaces for interacting with the P2P network, and are currently used in the `HeaderStage` and `BodyStage`.