cmd/puppeth, vendor: update ssh, manage server keys (#14398)

cmd/puppeth/ssh.go

cmd/puppeth/wizard.go

cmd/puppeth/wizard_intro.go

cmd/puppeth/wizard_netstats.go

cmd/puppeth/wizard_network.go

vendor/golang.org/x/crypto/curve25519/cswap_amd64.s

vendor/golang.org/x/crypto/curve25519/curve25519.go

vendor/golang.org/x/crypto/ssh/certs.go

vendor/golang.org/x/crypto/ssh/client.go

vendor/golang.org/x/crypto/ssh/client_auth.go

vendor/golang.org/x/crypto/ssh/common.go

vendor/golang.org/x/crypto/ssh/doc.go

vendor/golang.org/x/crypto/ssh/handshake.go

vendor/golang.org/x/crypto/ssh/keys.go

vendor/golang.org/x/crypto/ssh/server.go

vendor/golang.org/x/crypto/ssh/streamlocal.go

vendor/golang.org/x/crypto/ssh/tcpip.go

vendor/golang.org/x/crypto/ssh/terminal/util_solaris.go

vendor/vendor.json