cli/command/registry: fakeClient: remove name for unused arg (revive)

cli/command/registry/login_test.go:37:26: unused-parameter: parameter 'ctx' seems to be unused, consider removing or renaming it as _ (revive)
    func (c fakeClient) Info(ctx context.Context) (types.Info, error) {
                             ^
    cli/command/registry/login_test.go:41:35: unused-parameter: parameter 'ctx' seems to be unused, consider removing or renaming it as _ (revive)
    func (c fakeClient) RegistryLogin(ctx context.Context, auth types.AuthConfig) (registrytypes.AuthenticateOKBody, error) {
                                      ^

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cli/command/registry/login_test.go

@@ -34,11 +34,11 @@ type fakeClient struct {
 	client.Client
 }
 
-func (c fakeClient) Info(ctx context.Context) (types.Info, error) {
+func (c fakeClient) Info(context.Context) (types.Info, error) {
 	return types.Info{}, nil
 }
 
-func (c fakeClient) RegistryLogin(ctx context.Context, auth types.AuthConfig) (registrytypes.AuthenticateOKBody, error) {
+func (c fakeClient) RegistryLogin(_ context.Context, auth types.AuthConfig) (registrytypes.AuthenticateOKBody, error) {
 	if auth.Password == expiredPassword {
 		return registrytypes.AuthenticateOKBody{}, fmt.Errorf("Invalid Username or Password")
 	}