Fix backup option from provider_backup_enabled to cloud_backup

[paikend]

Description

provider_backup_enabled is deprecated

25: provider_backup_enabled = true

This field is deprecated,please use cloud_backup instead

Use cloud_backup, Instead of provider_backup_enabled

Thanks :)

Link to any related issue(s):

Type of change:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Documentation fix/enhancement

Required Checklist:

• I have signed the MongoDB CLA
• I have read the Terraform contribution guidelines
• I have added tests that prove my fix is effective or that my feature works per HashiCorp requirements
• I have added any necessary documentation (if appropriate)
• I have run make fmt and formatted my code

Further comments

[themantissa]

Good catch, thank you!

[themantissa]

LGTM!