The License type for premium images (RHEL, RHEL for SAP,
SLES, SLES for SAP, Windows Server).
Values:
LICENSE_TYPE_UNSPECIFIED (0):
Unspecified (default value).
LICENSE_TYPE_DEFAULT (1):
Default Google Cloud licensing plan.
Licensing is charged per usage. This a good
value to start with.
LICENSE_TYPE_BRING_YOUR_OWN_LICENSE (2):
Bring-your-own-license (BYOL) plan. User
provides the OS license.
