eth: change snapshot extension registration failure to warning instead of error (#24475)

* core: Change Snapshot extension registration failed to Debug

* Update eth/handler.go
Co-authored-by: Martin Holst Swende <martin@swende.se>

eth/handler.go

@@ -474,7 +474,7 @@ func (h *handler) runSnapExtension(peer *snap.Peer, handler snap.Handler) error
 	defer h.peerWG.Done()
 
 	if err := h.peers.registerSnapExtension(peer); err != nil {
-		peer.Log().Error("Snapshot extension registration failed", "err", err)
+		peer.Log().Warn("Snapshot extension registration failed", "err", err)
 		return err
 	}
 	return handler(peer)