ci: Fix build_args

.github/workflows/build-and-push-docker-base-image.yml

@@ -37,8 +37,7 @@ jobs:
           context: .
           platforms: linux/amd64,linux/arm64,linux/arm/v7
           file: Dockerfile.base
-          build_args:
+          build_args: ALPINE_VERSION=${{ env.ALPINE_VERSION }}
-            - ALPINE_VERSION=${{ env.ALPINE_VERSION }}
           push: true
           tags: |
             ghcr.io/plankanban/planka:base-latest