p2p/simulations: remove stale information about docker adapter (#29874)

p2p/simulations/adapters/types.go

@@ -42,7 +42,6 @@ import (
 //
 //   - SimNode, an in-memory node in the same process
 //   - ExecNode, a child process node
-//   - DockerNode, a node running in a Docker container
 type Node interface {
 	// Addr returns the node's address (e.g. an Enode URL)
 	Addr() []byte

p2p/simulations/examples/ping-pong.go

@@ -33,7 +33,7 @@ import (
 	"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
 )
 
-var adapterType = flag.String("adapter", "sim", `node adapter to use (one of "sim", "exec" or "docker")`)
+var adapterType = flag.String("adapter", "sim", `node adapter to use (one of "sim" or "exec")`)
 
 // main() starts a simulation network which contains nodes running a simple
 // ping-pong protocol