Use context during build to match Dockerfile expectations

.github/workflows/build-push.yml

@@ -41,15 +41,13 @@ jobs:
         # aka base build
         if [ ${{ inputs.dockerFile }} == "Dockerfile" ]; then
           echo "image=scyllaridae" >> $GITHUB_OUTPUT
+          echo "context=." >> $GITHUB_OUTPUT
           exit 0
         fi
 
-        # put the YML file in place so it's copied into the Docker container
         DIR=$(dirname "${{ inputs.dockerFile }}")
-        cp ./$DIR/scyllaridae.yml .
-        # name the docker image after the folder name prefixed by scyllaridae
-        # e.g. scyllaridae-curl
         echo "image=scyllaridae-$(basename $DIR)" >> $GITHUB_OUTPUT
+        echo "context=$DIR" >> $GITHUB_OUTPUT
       id: setup
 
     - id: 'auth'
@@ -71,8 +69,7 @@ jobs:
     - name: Build and push
       uses: docker/build-push-action@v5
       with:
-        context: .
-        file: ${{ inputs.dockerFile }}
+        context: ${{steps.setup.outputs.context}}
         build-args: |
           TAG=${{steps.extract_branch.outputs.branch}}
           DOCKER_REPOSITORY=us-docker.pkg.dev/${{ secrets.GCLOUD_PROJECT }}/public