eth: fix typo (ethereum#25161)

eth/handler.go

@@ -298,7 +298,7 @@ func newHandler(config *handlerConfig) (*handler, error) {
 }
 
 // runEthPeer registers an eth peer into the joint eth/snap peerset, adds it to
-// various subsistems and starts handling messages.
+// various subsystems and starts handling messages.
 func (h *handler) runEthPeer(peer *eth.Peer, handler eth.Handler) error {
 	// If the peer has a `snap` extension, wait for it to connect so we can have
 	// a uniform initialization/teardown mechanism