Filter dashboards faster with template variable available values

Datadog's Terraform provider v4.0.0 introduces significant improvements including support for managing Datadog Synthetics tests, monitors, and logs integrations directly through Terraform. This release focuses on enhanced resource coverage and simplified configuration, allowing for more robust and automated infrastructure-as-code management of Datadog resources. It also includes important breaking changes, so users are encouraged to review the migration guide before upgrading.