chore: fix GitHub secret names

Author: ldez

.github/workflows/release.yml

@@ -28,10 +28,10 @@ jobs:
 
       - name: Docker Login
         env:
-          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
-          DOCKER_TOKEN: ${{ secrets.DOCKER_TOKEN }}
+          DOCKERHUB_USERNAME: ${{ secrets.DOCKERHUB_USERNAME }}
+          DOCKERHUB_TOKEN: ${{ secrets.DOCKERHUB_TOKEN }}
         run: |
-          echo "${DOCKER_TOKEN}" | docker login --username "${DOCKER_USERNAME}" --password-stdin
+          echo "${DOCKERHUB_TOKEN}" | docker login --username "${DOCKERHUB_USERNAME}" --password-stdin
 
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v2