feat: update veo3 model version (#13524)

* feat: update veo3 model version

* feat: add prompt

Author: katiemn

genai/video_generation/requirements.txt

@@ -1 +1 @@
-google-genai==1.20.0
+google-genai==1.27.0

genai/video_generation/videogen_with_img.py

@@ -26,6 +26,7 @@ def generate_videos_from_image(output_gcs_uri: str) -> str:
 
     operation = client.models.generate_videos(
         model="veo-3.0-generate-preview",
+        prompt="Extreme close-up of a cluster of vibrant wildflowers swaying gently in a sun-drenched meadow.",
         image=Image(
             gcs_uri="gs://cloud-samples-data/generative-ai/image/flowers.png",
             mime_type="image/png",

genai/video_generation/videogen_with_txt.py

@@ -25,7 +25,7 @@ def generate_videos(output_gcs_uri: str) -> str:
     # output_gcs_uri = "gs://your-bucket/your-prefix"
 
     operation = client.models.generate_videos(
-        model="veo-3.0-generate-preview",
+        model="veo-3.0-generate-001",
         prompt="a cat reading a book",
         config=GenerateVideosConfig(
             aspect_ratio="16:9",