ci: Add allgreen job to signify overall workflow status

Rework the bors job (which signifies overall workflow status) into a more
generic job named allgreen.

Signed-off-by: Christopher Obbard <chris.obbard@collabora.com>

Author: obbardc

.github/workflows/ci.yml

@@ -89,11 +89,10 @@ jobs:
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
 
-
-# Job to key the bors success status against
-  bors:
-    name: bors
-    if: success()
+  # Job to key success status against
+  allgreen:
+    name: allgreen
+    if: always()
     needs:
       - check
       - fmt
@@ -102,5 +101,7 @@ jobs:
       - docker-image
     runs-on: ubuntu-latest
     steps:
-      - name: Mark the job as a success
-        run: exit 0
+      - name: Decide whether the needed jobs succeeded or failed
+        uses: re-actors/alls-green@release/v1
+        with:
+          jobs: ${{ toJSON(needs) }}