Migrate gsutil usage to gcloud storage (#13721)

* Migrate gsutil usage to gcloud storage

* Update startup-script.sh

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Co-authored-by: gurusai-voleti <gvoleti@google.com>

Author: bhandarivijay-png

compute/api/startup-script.sh

@@ -30,8 +30,8 @@ wget $IMAGE_URL
 convert * -pointsize 30 -fill white -stroke black -gravity center -annotate +10+40 "$TEXT" output.png
 
 # Create a Google Cloud Storage bucket.
-gsutil mb gs://$CS_BUCKET
+gcloud storage buckets create gs://$CS_BUCKET
 
 # Store the image in the Google Cloud Storage bucket and allow all users
 # to read it.
-gsutil cp -a public-read output.png gs://$CS_BUCKET/output.png
+gcloud storage cp --predefined-acl=publicRead output.png gs://$CS_BUCKET/output.png