ci: add var.DOCKERHUB_REGISTRY for login

Signed-off-by: Evan Wies <evan@neomantra.net>

Author: neomantra

.github/workflows/docker-publish.yml

@@ -26,6 +26,7 @@ on:
 
 env:
   GHCR_IMAGE: ${{ vars.GHCR_IMAGE || format('ghcr.io/{0}/openresty', github.repository_owner) }}
+  DOCKERHUB_REGISTRY: ${{ vars.DOCKERHUB_REGISTRY || 'docker.io' }}
   DOCKERHUB_IMAGE: ${{ vars.DOCKERHUB_IMAGE || 'docker.io/openresty/openresty' }}
 
 permissions:
@@ -278,7 +279,7 @@ jobs:
         if: vars.ENABLE_DOCKERHUB_MIRROR == 'true'
         uses: docker/login-action@v3
         with:
-          registry: ${{ env.DOCKERHUB_IMAGE }}
+          registry: ${{ env.DOCKERHUB_REGISTRY }}
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}
 
@@ -334,6 +335,7 @@ jobs:
         if: vars.ENABLE_DOCKERHUB_MIRROR == 'true'
         uses: docker/login-action@v3
         with:
+          registry: ${{ env.DOCKERHUB_REGISTRY }}
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}
 
@@ -402,6 +404,7 @@ jobs:
         if: vars.ENABLE_DOCKERHUB_MIRROR == 'true'
         uses: docker/login-action@v3
         with:
+          registry: ${{ env.DOCKERHUB_REGISTRY }}
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}