fix tests that failed because of inconsistent usage of crypto API

lib/common/destination/destination.go

@@ -31,7 +31,7 @@ Identical to KeysAndCert.
 //
 // https://geti2p.net/spec/common-structures#destination
 type Destination struct {
-	KeysAndCert
+	*KeysAndCert
 }
 
 // Base32Address returns the I2P base32 address for this Destination.

lib/common/router_identity/router_identity.go

@@ -28,7 +28,7 @@ Identical to KeysAndCert.
 //
 // https://geti2p.net/spec/common-structures#routeridentity
 type RouterIdentity struct {
-	KeysAndCert
+	*KeysAndCert
 }
 
 // ReadRouterIdentity returns RouterIdentity from a []byte.

lib/transport/ntcp/session.go

@@ -1,6 +1,7 @@
 package ntcp
 
 import (
+	"crypto/rand"
 	"math/big"
 	"time"
 
@@ -9,8 +10,6 @@ import (
 	"github.com/go-i2p/go-i2p/lib/transport/noise"
 	"github.com/go-i2p/go-i2p/lib/transport/obfs"
 
-	"crypto/rand"
-
 	"github.com/samber/oops"
 )