cleanup unstable workflow

.github/workflows/release_unstable.yml

@@ -1,4 +1,4 @@
-name: Publish Dotclear unstable image to Docker Hub
+name: Build and push dev image
 
 on:
   schedule:
@@ -6,12 +6,11 @@ on:
   workflow_dispatch:
 
 env:
-  IMAGE_NAME: jcpd/docker-dotclear:dev
+  DOTCLEAR_IMAGE: jcpd/docker-dotclear
   DOTCLEAR_CANAL: unstable
 
 jobs:
   push_to_docker_hub:
-    name: Push Docker image to registry
     runs-on: ubuntu-latest
     permissions:
       packages: write
@@ -37,7 +36,7 @@ jobs:
           context: .
           sbom: true
           push: true
-          tags: ${{ env.IMAGE_NAME }}
+          tags: ${{ env.DOTCLEAR_IMAGE }}:dev
           build-args: CANAL=${{ env.DOTCLEAR_CANAL }}
           platforms: linux/386,linux/amd64,linux/arm/V6
 
@@ -52,5 +51,5 @@ jobs:
           message: |
             Image successfully generated.
             __Repository:__ ${{github.repository}}
-            __Image:__ ${{ env.IMAGE_NAME }}
+            __Image:__ ${{ env.DOTCLEAR_IMAGE }}
             __Canal:__ ${{ env.DOTCLEAR_CANAL }}