fix(ci): fix ci rules

Author: pedrobrantes

.github/workflows/ci.yml

@@ -13,10 +13,10 @@ jobs:
   build-docker-image:
     if: |
       (github.event_name == 'push' || github.event_name == 'pull_request') &&
-      (contains(github.event.head_commit.modified, 'nix_test_env/Dockerfile') ||
-       contains(github.event.head_commit.added,    'nix_test_env/Dockerfile') ||
-       contains(github.event.head_commit.added,    'nix_test_env/docker_entrypoint.sh') ||
-       contains(github.event.head_commit.modified, 'nix_test_env/docker_entrypoint.sh'))
+      (contains(github.event.commits[0].modified, 'nix_test_env/Dockerfile') ||
+        contains(github.event.commits[0].added, 'nix_test_env/Dockerfile') ||
+        contains(github.event.commits[0].added, 'nix_test_env/docker_entrypoint.sh') ||
+        contains(github.event.commits[0].modified, 'nix_test_env/docker_entrypoint.sh'))
 
     runs-on: ubuntu-latest
     outputs:
@@ -49,8 +49,8 @@ jobs:
       - name: Debug event
         run: |
           echo "Event name: ${{ github.event_name }}"
-          echo "Modified files: ${{ github.event.head_commit.modified }}"
-          echo "Added files: ${{ github.event.head_commit.added }}"
+          echo "Modified files: ${{ github.event.commits[0].modified }}"
+          echo "Added files: ${{ github.event.commits[0].added }}"
 
   tests:
     runs-on: ubuntu-latest
@@ -63,13 +63,11 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Download Docker image artifact
-        if: needs.build-docker-image.outputs.build_ran == 'true'
         uses: actions/download-artifact@v4
         with:
           name: nix-docker-image
 
       - name: Load Docker image
-        if: needs.build-docker-image.outputs.build_ran == 'true'
         run: |
           docker load -i nix-image.tar