tests/resource/aws_autoscaling_group: Fix typo in TestAccAWSAutoScalingGroup_LoadBalancers configuration (#11716)
tests/resource/aws_autoscaling_group: Fix typo in TestAccAWSAutoScalingGroup_LoadBalancers configuration (#11716)

Reference: https://github.com/terraform-providers/terraform-provider-aws/commit/3716d83741c8f4f67a01364f538a72305fa1a789

Previously in the acceptance testing:

```
--- FAIL: TestAccAWSAutoScalingGroup_LoadBalancers (1.02s)
    testing.go:640: Step 0 error: Argument or block definition required: On /opt/teamcity-agent/temp/buildTmp/tf-test387330890/main.tf line 17: An argument or block definition is required here.
```

Output from acceptance testing:

```
--- PASS: TestAccAWSAutoScalingGroup_LoadBalancers (667.70s)
```
kjmkznr/terraform-provider-aws,terraform-providers/terraform-provider-aws,terraform-providers/terraform-provider-aws,terraform-providers/terraform-provider-aws,terraform-providers/terraform-provider-aws,kjmkznr/terraform-provider-aws,kjmkznr/terraform-provider-aws,kjmkznr/terraform-provider-aws