fix double ref

Author: roni-frantchi

src/index.js

@@ -106,9 +106,9 @@ module.exports = function (serverless) {
                         Properties: {
                             StageName: deployment.Properties.StageName,
                             Description: `${deployment.Properties.StageName} stage of ${serverless.service.service}`,
-                            RestApiId: {
-                                Ref: _.get(serverless, 'service.provider.apiGateway.restApiId', 'ApiGatewayRestApi')
-                            },
+                            RestApiId: _.get(serverless, 'service.provider.apiGateway.restApiId', {
+                                Ref: 'ApiGatewayRestApi'
+                            }),
                             DeploymentId: {
                                 Ref: deploymentKey
                             },

test/spec/index.spec.js

@@ -499,7 +499,7 @@ describe('The `serverless-api-stage` plugin', function () {
                 pluginInstance.hooks['before:deploy:deploy']();
             });
             it('Adds an API Gateway Stage resource to the CloudFormation template with specified variables and settings', function () {
-                expect(serverless.service.provider.compiledCloudFormationTemplate.Resources.ApiGatewayStageTesting.Properties.RestApiId.Ref).to.equal(serverless.service.provider.apiGateway.restApiId);
+                expect(serverless.service.provider.compiledCloudFormationTemplate.Resources.ApiGatewayStageTesting.Properties.RestApiId).to.equal(serverless.service.provider.apiGateway.restApiId);
             });
         });
     });