Roll up all matrix results into 1 spec_legacy_ruby_all job

.github/workflows/ci.yml

@@ -40,3 +40,15 @@ jobs:
           bundler: "1.17.3"
           bundler-cache: true
       - run: bundle exec rake test
+  spec_all:
+    name: "Test / Ruby (All)"
+    runs-on: ubuntu-latest
+    needs: [spec_legacy_ruby, spec_legacy_ruby_19]
+    if: always()
+    steps:
+      - name: All tests ok
+        if: ${{ !(contains(needs.*.result, 'failure')) }}
+        run: exit 0
+      - name: Some tests failed
+        if: ${{ contains(needs.*.result, 'failure') }}
+        run: exit 1