.github/workflows/ci-linux.yml (standard-sitepackages): Only test pla…

…tforms with usable system python

.github/workflows/ci-linux.yml

@@ -78,7 +78,38 @@ jobs:
       targets: build doc-html
       targets_optional: ptest
       tox_packages_factors: >-
-          ["standard-sitepackages"]
+        ["standard-sitepackages"]
+      # Only test systems with a usable system python (>= 3.9)
+      tox_system_factors: >-
+        ["ubuntu-jammy",
+         "ubuntu-kinetic",
+         "ubuntu-lunar",
+         "ubuntu-mantic",
+         "debian-bullseye",
+         "debian-bookworm",
+         "debian-trixie",
+         "debian-sid",
+         "linuxmint-21",
+         "linuxmint-21.1",
+         "linuxmint-21.2",
+         "fedora-33",
+         "fedora-34",
+         "fedora-35",
+         "fedora-36",
+         "fedora-37",
+         "fedora-38",
+         "fedora-39",
+         "centos-stream-8-python3.9",
+         "centos-stream-9-python3.9",
+         "almalinux-8-python3.9",
+         "gentoo-python3.10",
+         "gentoo-python3.11",
+         "archlinux-latest",
+         "opensuse-15.4-gcc_11-python3.10",
+         "opensuse-15.5-gcc_11-python3.11",
+         "opensuse-tumbleweed-python3.10",
+         "opensuse-tumbleweed",
+         "debian-bullseye-i386"]
       docker_push_repository: ghcr.io/${{ github.repository }}/
       max_parallel: 10