Replace deprecated command with environment file

Signed-off-by: jongwooo <[email protected]>

.github/workflows/main.yml

@@ -39,7 +39,7 @@ jobs:
 
       - name: Get current date
         id: date
-        run: echo "::set-output name=date::$(date +'%Y%m%d')"
+        run: echo "date=$(date +'%Y%m%d')" >> $GITHUB_OUTPUT
       - name: Configure Github Package Registry
         run: echo ${{ secrets.GITHUB_TOKEN }} | docker login docker.pkg.github.com -u $GITHUB_ACTOR --password-stdin
       - name: Install dependencies