workflows/build-ci-container: Make sure to only test local containers (#120827)

The container test is run before we create the :latest tag, so we should
not try testing this, otherwise it will pull the :latest tag from the
github registry, and won't test the container we just built.

Author: tstellar

.github/workflows/build-ci-container.yml

@@ -59,8 +59,9 @@ jobs:
 
       - name: Test Container
         run: |
-          for image in ${{ steps.vars.outputs.container-name-tag }} ${{  steps.vars.outputs.container-name }}; do
-            podman run --rm -it $image /usr/bin/bash -x -c 'cd $HOME && printf '\''#include <iostream>\nint main(int argc, char **argv) { std::cout << "Hello\\n"; }'\'' | clang++ -x c++ - && ./a.out | grep Hello'
+          for image in ${{ steps.vars.outputs.container-name-tag }}; do
+            # Use --pull=never to ensure we are testing the just built image.
+            podman run --pull=never --rm -it $image /usr/bin/bash -x -c 'cd $HOME && printf '\''#include <iostream>\nint main(int argc, char **argv) { std::cout << "Hello\\n"; }'\'' | clang++ -x c++ - && ./a.out | grep Hello'
           done
 
   push-ci-container: