feat: Introduce tracks and thumbnails fields for FaceDetectionAnnotations (#90)

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PiperOrigin-RevId: 346664095
Source-Link: googleapis/googleapis@468a94a
PiperOrigin-RevId: 346138329
Source-Link: googleapis/googleapis@674ec0e
Source-Link: googleapis/synthtool@7fcc405

Author: yoshi-automation

google/cloud/videointelligence_v1/proto/video_intelligence.proto

@@ -551,10 +551,18 @@ class FaceDetectionAnnotation(proto.Message):
     r"""Face detection annotation.
 
     Attributes:
+        tracks (Sequence[~.video_intelligence.Track]):
+            The face tracks with attributes.
+        thumbnail (bytes):
+            The thumbnail of a person's face.
         version (str):
             Feature version.
     """
 
+    tracks = proto.RepeatedField(proto.MESSAGE, number=3, message="Track",)
+
+    thumbnail = proto.Field(proto.BYTES, number=4)
+
     version = proto.Field(proto.STRING, number=5)