ci: run on ubuntu-latest; assert docker availability instead of installing

.gitea/workflows/dev.yml

@@ -5,7 +5,7 @@ on:
       - '*'
 jobs:
   build-and-push:
-    runs-on: docker
+    runs-on: ubuntu-latest
     steps:
       - name: Checkout
         uses: actions/checkout@v4
@@ -41,15 +41,15 @@ jobs:
           git rev-parse --abbrev-ref HEAD || true
           if [ -f .gitmodules ]; then echo ".gitmodules present"; cat .gitmodules; else echo "NO .gitmodules"; fi
           git submodule status || true
-      - name: Install docker client
-        run: |
-          apt-get update -y
-          apt-get install -y docker.io
       - name: Docker info
         run: |
           which docker || true
-          docker version || true
-          docker info || true
+          if ! command -v docker >/dev/null 2>&1; then
+            echo "Docker n'est pas disponible sur ce runner (ubuntu-latest)." >&2
+            exit 1
+          fi
+          docker version
+          docker info
       - name: Build and push images
         env:
           REGISTRY: git.4nkweb.com