Actions was in the way

.github/workflows/push-cibuild.yml

@@ -3,19 +3,28 @@ name: "GitHub Pages Health Check Tests"
 permissions:
   contents: read
 jobs:
-  build:
-    name: "GitHub Pages Health Check Tests"
+  # Run sequential jobs because /script/test-redirections needs specific ports opened on the runner
+  # and we cannot do that in parallel.
+  ruby_3_0:
     runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        ruby:
-          - '3.0'
-          - '3.1'
-          - '3.2'
     steps:
     - uses: actions/checkout@master
-    - name: script/cibuild-docker
-      run: script/cibuild-docker
+    - run: script/cibuild-docker
       env:
-        RUBY_VERSION: ${{ matrix.ruby }}
+        RUBY_VERSION: 3.0
+  ruby_3_1:
+    runs-on: ubuntu-latest
+    needs: ruby_3_0
+    steps:
+    - uses: actions/checkout@master
+    - run: script/cibuild-docker
+      env:
+        RUBY_VERSION: 3.1
+  ruby_3_2:
+    runs-on: ubuntu-latest
+    needs: ruby_3_1
+    steps:
+    - uses: actions/checkout@master
+    - run: script/cibuild-docker
+      env:
+        RUBY_VERSION: 3.2