CI: Test if we can build puppetboard

In our normal test pipeline, we didn't verify if we can properly build
the package. because of that, the last 6.0.0 release failed:

```
Run python setup.py build sdist bdist_wheel
Traceback (most recent call last):
  File "/home/runner/work/puppetboard/puppetboard/setup.py", line 3, in <module>
    from setuptools.command.test import test as TestCommand
ModuleNotFoundError: No module named 'setuptools'
```

.github/workflows/publish-to-pypi.yml

@@ -17,11 +17,9 @@ jobs:
         with:
           python-version: 3.12
       - name: Install dependencies
-        run: |
-          pip install wheel
+        run: pip install wheel
       - name: Build
-        run: |
-          python setup.py build sdist bdist_wheel
+        run: python setup.py build sdist bdist_wheel
       - name: Publish distribution 📦 to PyPI
         uses: pypa/[email protected]
         with:

.github/workflows/tests.yml

@@ -12,7 +12,6 @@ jobs:
     runs-on: ubuntu-latest
 
     strategy:
-      max-parallel: 5
       matrix:
         python-version: [3.9, '3.10', 3.11, 3.12, 3.13]
 
@@ -37,6 +36,25 @@ jobs:
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
           fail_ci_if_error: true
+      - name: Build
+        run: python setup.py build sdist bdist_wheel
+
+  # this uses the same commands as in our release pipeline and ensures that we can still build puppetboard
+  test-build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: [3.9, '3.10', 3.11, 3.12, 3.13]
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python ${{ matrix.python-version }
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }
+      - name: Install dependencies
+        run: pip install wheel
+      - name: Build
+        run: python setup.py build sdist bdist_wheel
 
   build_docker_image:
     name: 'Test building a container'