store date in github_date

.github/workflows/docker.yml

@@ -13,7 +13,7 @@ jobs:
     steps:
       - name: Get current date
         id: date
-        run: echo "::set-output name=date::$(date +'%Y-%m-%d')"
+        run: echo "{date}={$(date +'%Y-%m-%d')}" >> $GITHUB_STATE
       - name: Login to GitHub Container registry
         uses: docker/login-action@v3
         env:
@@ -28,6 +28,5 @@ jobs:
         uses: docker/build-push-action@v5
         with:
           context: .
-          file: Dockerfile
           push: true
           tags: ghcr.io/wwu-trap/cjp8:${{ steps.date.outputs.date }}