[Feature] Maintenance Window via IaC

[kayrenfa-gt]

Is your feature request related to a problem? Please describe.
Will be great if maintenance window is supported via IaC. this can be useful for regular maintenance than doing clickops to create this.

common problem such as kubernetes node scale down to 0 during non-peak period resulting alerts triggered by synthetic monitor

Describe the resource you would like to have implemented.
https://www.elastic.co/docs/api/doc/kibana/operation/operation-post-maintenance-window
/api/maintenance_window
GET, POST, PATCH/PUT, DELETE

Describe the solution you'd like
A terraform resource for us to create regular maintenance window.
Not sure how it can work for one off window when the period is over.

Describe alternatives you've considered
Using API to create

Additional context
Nil

[tobio]

@kayrenfa-gt this has been added in #1224 and will be available in the next release which should be in the next few weeks.