Revert sending SSH certificate as a separate protocol

Gitlab Rails now restricts SSH protocol access via an
additional boolean setting rather than a separate Git
protocol

internal/gitlabnet/accessverifier/client.go

@@ -13,9 +13,8 @@ import (
 )
 
 const (
-	sshProtocol     = "ssh"
-	sshCertProtocol = "ssh_certificates"
-	anyChanges      = "_any"
+	sshProtocol = "ssh"
+	anyChanges  = "_any"
 )
 
 type Client struct {
@@ -93,10 +92,6 @@ func (c *Client) Verify(ctx context.Context, args *commandargs.Shell, action com
 		NamespacePath: args.Env.NamespacePath,
 	}
 
-	if args.Env.NamespacePath != "" {
-		request.Protocol = sshCertProtocol
-	}
-
 	if args.GitlabUsername != "" {
 		request.Username = args.GitlabUsername
 	} else if args.GitlabKrb5Principal != "" {

internal/gitlabnet/accessverifier/client_test.go

@@ -266,7 +266,6 @@ func setup(t *testing.T, userResponses, keyResponses map[string]testResponse) *C
 					_, err := w.Write(tr.body)
 					require.NoError(t, err)
 					require.Equal(t, namespace, requestBody.NamespacePath)
-					require.Equal(t, sshCertProtocol, requestBody.Protocol)
 				} else if tr, ok := userResponses[requestBody.Krb5Principal]; ok {
 					w.WriteHeader(tr.status)
 					_, err := w.Write(tr.body)