feat: A new field last_vulnerability_update_time is added to message .grafeas.v1.DiscoveryOccurrence (#32397)

* feat: A new field `last_vulnerability_update_time` is added to message `.grafeas.v1.DiscoveryOccurrence`

PiperOrigin-RevId: 861286340

Source-Link: googleapis/googleapis@70da46f

Source-Link: googleapis/googleapis-gen@dab19f1
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grafeas-v1/lib/grafeas/v1/discovery_pb.rb

@@ -67,6 +67,9 @@ class DiscoveryNote
     # @!attribute [rw] files
     #   @return [::Array<::Grafeas::V1::DiscoveryOccurrence::File>]
     #     Files that make up the resource described by the occurrence.
+    # @!attribute [rw] last_vulnerability_update_time
+    #   @return [::Google::Protobuf::Timestamp]
+    #     The last time vulnerability scan results changed.
     class DiscoveryOccurrence
       include ::Google::Protobuf::MessageExts
       extend ::Google::Protobuf::MessageExts::ClassMethods