fix docker login

.github/workflows/build.yml

@@ -20,10 +20,10 @@ jobs:
           go-version: '^1.22.5'
       - run: go version
       - name: Login to Package Registry
-        uses: docker/login-action@v2
+        uses: docker/login-action@v3
         with:
           registry: git.wittern.io
-          username: ${{ secrets.DOCKER_USERNAME }}
+          username: ${{ github.actor }}
           password: ${{ secrets.DOCKER_PASSWORD }}
       - name: Build the Docker image
         run: |