github/workflows: Keep Debian on ubuntu-latest runners

See: toolbx-images#129 (comment)

Author: travier

.github/workflows/debian.yaml

@@ -38,7 +38,7 @@ jobs:
       matrix:
         release: ['10', '11', '12', 'testing', 'unstable']
 
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-latest
     steps:
       - name: Checkout
         uses: actions/checkout@v4