chore(ci): separate jobs

Author: mpsq

.github/workflows/build.yml

@@ -1,20 +1,13 @@
 on: push
 
 jobs:
-  build:
+  image:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
       - name: Set up Docker Buildx
         id: buildx
         uses: docker/setup-buildx-action@master
-      - name: Cache Docker layers
-        uses: actions/cache@v2
-        with:
-          path: /tmp/.buildx-cache
-          key: ${{ runner.os }}-buildx-${{ github.sha }}
-          restore-keys: |
-            ${{ runner.os }}-buildx-
       - name: Login to GitHub Container Registry
         uses: docker/login-action@v1
         with:
@@ -28,9 +21,13 @@ jobs:
           builder: ${{ steps.buildx.outputs.name }}
           push: true
           tags: mpsq/emacs-native-comp-wayland-builder:latest
-          cache-from: type=local,src=/tmp/.buildx-cache
-          cache-to: type=local,dest=/tmp/.buildx-cache
+
+  artifact:
+    runs-on: ubuntu-latest
+    needs: [image]
+    container: mpsq/emacs-native-comp-wayland-builder:latest
+    steps:
       - uses: actions/upload-artifact@v2
         with:
           name: emacs-native-comp-git-enhanced
-          path: /home/runner/work/_temp/_github_workflow/emacs-native-comp-git-enhanced*
+          path: /home/pcr/emacs-native-comp-git-enhanced*