chore: update debian version for samples

attempt to unblock samples tests

samples/compute/create_instance.py

diff --git a/samples/compute/create_instance.py b/samples/compute/create_instance.py
index f0bd86b..9e03087 100644
--- a/samples/compute/create_instance.py
+++ b/samples/compute/create_instance.py
@@ -43,7 +43,7 @@
     # Get the latest Debian Jessie image.
     image_response = (
         compute.images()
-        .getFromFamily(project="debian-cloud", family="debian-11")
+        .getFromFamily(project="debian-cloud", family="debian-12")
         .execute()
     )
     source_disk_image = image_response["selfLink"]