Support denyMaintenancePeriod field in SQLInstance

[MoElkhidir]

Checklist

• [ x ] I did not find a related open issue.
• [ x ] I did not find a solution in the troubleshooting guide: (https://cloud.google.com/config-connector/docs/troubleshooting)
• [ x ] If this issue is time-sensitive, I have submitted a corresponding issue with GCP support.

Bug Description

Exporting an imperative SqlInstnace resource using config-connector doesn't include DenyMaintenanceWindow in the yaml configuration output

Additional Diagnostic Information

Kubernetes Cluster Version

Client Version: v1.22.4
Server Version: v1.21.9-gke.1002

Config Connector Version

1.71.0

Steps to Reproduce

Steps to reproduce the issue

1. Create a SqlInstnace using Cloud Console.
2. Manually set the DenyMaintenancePeriod for the instance in the console.
3. (optional) Use gcloud CLI to describe the imperative instance and save it.
4. Use Config-Connector to export the instance to be declaratively imported.
5. User Kubectl to import the instance to be declaratively managed.
6. (optional) Use gcloud CLI to describe the now declaratively-managd instance and save it.
7. Compare the two instance descriptions from 3 and 6 Or navigate to Google Cloud Console and observe for DenyMaintenancePeriods to have been removed.

[caieo]

Hi @moe-elkhidir, I'm going to actually mark this as an enhancement and not a bug because technically KCC is behaving as expected. It looks like the DenyMaintenancePeriod is a newer field that is not yet added in our CRD. In order to support this new field, we rely on Terraform adding it to their SQLInstance config. It looks like there is already an open issue here for it: hashicorp/terraform-provider-google#11287 . Feel free to chime in or 👍 that TF issue. Once the field is supported in TF, it should be a one or two week delay before it's added into KCC.