ci: fix gitlab registry token

Author: christophwitzko

.github/workflows/ci.yml

@@ -60,8 +60,8 @@ jobs:
       - uses: docker/login-action@v1
         with:
           registry: registry.gitlab.com
-          username: ${{ secrets.GITLAB_USER }}
-          password: ${{ secrets.GITLAB_TOKEN }}
+          username: ${{ secrets.GITLAB_REGISTRY_USER }}
+          password: ${{ secrets.GITLAB_REGISTRY_TOKEN }}
       - uses: go-semantic-release/action@v1
         with:
           bin: ./semantic-release