Remove beta tag from gossipsub 1.2 (#6344)

* Remove the beta tag from gossipsub v1.2

* fix clippy

* Merge branch 'unstable' into remove-beta-tag

beacon_node/lighthouse_network/gossipsub/src/behaviour.rs

@@ -2716,7 +2716,7 @@ where
             };
 
             // Only gossipsub 1.2 peers support IDONTWANT.
-            if peer.kind != PeerKind::Gossipsubv1_2_beta {
+            if peer.kind != PeerKind::Gossipsubv1_2 {
                 continue;
             }