ci: use jq to check the status of dependencies in the report job

.github/workflows/ci.yml

@@ -14,15 +14,16 @@ jobs:
       - package-crates
       - build-dist-linux
       - build-dist-windows
+    # 'always()' is needed because GitHub treats a skipped job (due to a failed
+    # dependency) a success.
     if: always()
     runs-on: ubuntu-20.04
     steps:
-      - name: Report success
-        if: "!contains(needs.*.result, 'failure') && !contains(needs.*.result, 'cancelled')"
-        run: exit 0
-      - name: Report failure
-        if: "contains(needs.*.result, 'failure') || contains(needs.*.result, 'cancelled')"
-        run: exit 1
+      - name: Report status
+        env:
+          NEEDS_JSON: ${{ toJson(needs) }}
+        # Make sure all dependencies succeeded.
+        run: jq --exit-status 'all(.result == "success")' <<< "$NEEDS_JSON"
 
   lint-aux:
     runs-on: ubuntu-20.04