Updated worker base image to Debian 12. (#8853)

Author: isoos

CHANGELOG.md

@@ -2,6 +2,8 @@ Important changes to data models, configuration, and migrations between each
 AppEngine version, listed here to ease deployment and troubleshooting.
 
 ## Next Release (replace with git tag when deployed)
+ * Bump runtimeVersion to `2025.07.14`.
+ * Note: Updated worker base image to use Debian 12.
 
 ## `20250708t090800-all`
  * Bump runtimeVersion to `2025.07.04`.

Dockerfile.worker

@@ -1,4 +1,4 @@
-FROM gcr.io/google-containers/debian-base-amd64:v2.0.0
+FROM docker.io/debian:12
 
 RUN apt-get update && \
   apt-get upgrade -y && \

app/lib/shared/versions.dart

@@ -24,10 +24,10 @@ final RegExp runtimeVersionPattern = RegExp(r'^\d{4}\.\d{2}\.\d{2}$');
 /// when the version switch happens.
 const _acceptedRuntimeVersions = <String>[
   // The current [runtimeVersion].
-  '2025.07.04',
+  '2025.07.14',
   // Fallback runtime versions.
+  '2025.07.04',
   '2025.07.01',
-  '2025.06.20',
 ];
 
 /// Sets the current runtime versions.