feat: (PSKD-709) Add Support for NetApp Volumes

[riragh]

Changes:

This PR makes the required changes to add support for Google NetApp volumes.
Resources were added using the NetApp Volume on Google Terraform provider

New variable storage_type_backend has been introduced to choose the backend type. To use Google NetApp volume user is expected to set storage_type_backend = netapp.

If storage_type=standard the default is "nfs"; If storage_type=ha the default is "filestore".
Valid Values: "nfs" if storage_type=standard; "filestore" or "netapp" if storage_type=ha.

Tests:

Verified following scenarios:

Scenario	Description	Order Cadence	Verification
1	Defaults	Fast 2020	storage_type is "standard", storage_type_backend is "nfs". Viya deployment is successful.
2	storage_type = "ha"	Fast 2020	storage_type is "ha", storage_type_backend is "filestore". Viya deployment is successful.
3	storage_type = "ha", storage_type_backend = "netapp", netapp_protocols = ["NFSV3"]	Fast 2020	storage_type is "ha", storage_type_backend is "netapp". NFS protocol is set to NFSv3. Viya deployment is successful.
4	storage_type = "ha", storage_type_backend = "netapp", netapp_protocols = ["NFSV4"]	Fast 2020	storage_type is "ha", storage_type_backend is "netapp". NFS protocol is set to NFSv4.1. Viya deployment runs into mount setup issue for CAS and launcher. See internal ticket for details.