allow pip to break system packages when installin pykickstart

Ubuntu 24.04 by default protects system packages, which is good, but in
CI we just don't care enough to create a venv.

.github/workflows/foreman.yml

@@ -115,7 +115,7 @@ jobs:
         if: contains(matrix.task, 'compile')
       - name: Install external test dependencies
         run: |
-          pip3 install pykickstart
+          pip3 install --break-system-packages pykickstart
           sudo apt-get -qq -y install --no-install-recommends grub-common
         if: contains(matrix.task, 'external')
       - name: Prepare test env