Run test-app CI job on Ubuntu (not Debian container)

Zig builds fail for some reason and perhaps it's related to running in a
container?

.github/workflows/test-app.yml

@@ -8,17 +8,15 @@ on:
 jobs:
   test-app:
     runs-on: ubuntu-latest
-    container:
-      image: debian:experimental
     steps:
       - name: "Download .deb files"
         uses: actions/download-artifact@v3
         with:
           name: acton-debs
       - name: "Install acton from .deb"
         run: |
-          apt update
-          apt install -y ./deb/acton_*.deb
+          sudo apt update
+          sudo apt install -y ./deb/acton_*.deb
           acton --version
       - name: "Clone app repo"
         uses: actions/checkout@v4