fix(aws-elasticloadbalancingv2): unhealthy threshold (#1145)

Fix bug where unhealthy threshold count would not be reflected
in CloudFormation properties.

Author: rix0rrr

packages/@aws-cdk/aws-elasticloadbalancingv2/lib/shared/base-target-group.ts

@@ -194,6 +194,7 @@ export abstract class BaseTargetGroup extends cdk.Construct implements ITargetGr
       healthCheckProtocol: new cdk.Token(() => this.healthCheck && this.healthCheck.protocol),
       healthCheckTimeoutSeconds: new cdk.Token(() => this.healthCheck && this.healthCheck.timeoutSeconds),
       healthyThresholdCount: new cdk.Token(() => this.healthCheck && this.healthCheck.healthyThresholdCount),
+      unhealthyThresholdCount: new cdk.Token(() => this.healthCheck && this.healthCheck.unhealthyThresholdCount),
       matcher: new cdk.Token(() => this.healthCheck && this.healthCheck.healthyHttpCodes !== undefined ? {
         httpCode: this.healthCheck.healthyHttpCodes
       } : undefined),

packages/@aws-cdk/aws-elasticloadbalancingv2/test/alb/test.listener.ts

@@ -287,13 +287,15 @@ export = {
       targets: [new FakeSelfRegisteringTarget(stack, 'Target', vpc)]
     });
     group.configureHealthCheck({
+      unhealthyThresholdCount: 3,
       timeoutSeconds: 3600,
       intervalSecs: 30,
       path: '/test',
     });
 
     // THEN
     expect(stack).to(haveResource('AWS::ElasticLoadBalancingV2::TargetGroup', {
+      UnhealthyThresholdCount: 3,
       HealthCheckIntervalSeconds: 30,
       HealthCheckPath: "/test",
       HealthCheckTimeoutSeconds: 3600,