[CBR] - Add CrossRegion Replication functionality

[uli-schneider]

Description of the enhancement

Please extend following providers: https://registry.terraform.io/providers/opentelekomcloud/opentelekomcloud/latest/docs/resources/cbr_policy_v3 https://registry.terraform.io/providers/opentelekomcloud/opentelekomcloud/latest/docs/resources/cbr_vault_v3

to be able to setting up CBR-Cross Region functionaltiy to CBR.

https://www.open-telekom-cloud.com/en/support/release-notes/cbr-supports-geo-redundant-backups https://community.open-telekom-cloud.com/community?id=community_blog&sys_id=b80a47c61394d610d15a246ea6744134

Seems that for the policy the parameters: destination_project_id, destination_region are missing and not documented. https://docs.otc.t-systems.com/cloud-backup-recovery/api-ref/cbr_apis/policies/creating_a_policy.html#createpolicy

The Vault needs a field for the replication policy.

Please add this also to terraform documentation.

[anton-sidelnikov]

Added in latest release