Use matrix to run tests on all folders

.github/workflows/tests.yml

@@ -5,6 +5,9 @@ on:
 
 jobs:
   build_and_test:
+    strategy:
+      matrix:
+        folder: ["04", "05", "06", "07", "08", "09", "10", "11", "12", "13", "14", "15", "16", "17", "18", "19"]
     runs-on: macos-14
     steps:
       - name: Check Xcode version
@@ -13,8 +16,8 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v3
 
-      - name: Test
+      - name: Test examples ${{ matrix.folder }}
         run: |
           brew install xcodegen
-          cd ./04-tdd-in-the-real-world
+          cd "./${{ matrix.folder }}*"
           make