feat(advisorynotifications): adding notification types to advisorynot…

…ifications.googleapis.com libraries (#8361)

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adding NOTIFICATION_TYPE_SECURITY_MSA and NOTIFICATION_TYPE_THREAT_HORIZONS values to NotificationType enum of advisorynotifications.googleapis.com Cloud Client library

PiperOrigin-RevId: 552514004

Source-Link: https://togithub.com/googleapis/googleapis/commit/9ae0377ab01a95279cd65116849207bab9de44ce

Source-Link: https://togithub.com/googleapis/googleapis-gen/commit/ca2d7184904e934c03cfc3e49caece34f2e86006
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