Try to avoid python version interference and add a similar Ubuntu LTS target

for comparison.

Author: jonasbardino

.github/workflows/python-c-ext-sanity-check.yml

@@ -73,6 +73,28 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: "3.x"
+      - name: Set up git, findutils and make with apt
+        run: |
+          sudo apt install -y git findutils make
+      - name: Install dependencies
+        run: |
+          sudo apt install -y libnss3-dev libpam-dev splint
+      # We may need git installed to get a full repo clone rather than unpacked archive
+      - name: Check out source repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0  # This is necessary to get the commits
+      - name: Lint with splint
+        run: |
+          # NOTE: we only run splint error check for changed c files to limit noise
+          # NOTE: point splint to Ubuntu's custom /usr/include/python3.x for Python.h
+          echo "Lint changed code files: $(git diff --diff-filter=ACMRTB --name-only HEAD^1 -- | grep -E '\.(c|h)$')"
+          git diff --diff-filter=ACMRTB --name-only HEAD^1 -- | grep -E '\.(c|h)$' | xargs -r splint +posixlib -D__gnuc_va_list=va_list $(python3-config --includes)
+
+  lint-c-ext-python3-ubuntu24.04:
+    name: Sanity check c-extension module code in latest Ubuntu LTS python3
+    runs-on: ubuntu-24.04
+    steps:
       - name: Set up git, findutils and make with apt
         run: |
           sudo apt install -y git findutils make
@@ -91,7 +113,7 @@ jobs:
           echo "Lint changed code files: $(git diff --diff-filter=ACMRTB --name-only HEAD^1 -- | grep -E '\.(c|h)$')"
           git diff --diff-filter=ACMRTB --name-only HEAD^1 -- | grep -E '\.(c|h)$' | xargs -r splint +posixlib -D__gnuc_va_list=va_list $(python3-config --includes)
 
-  lint-python3-rocky9:
+  lint-c-ext-python3-rocky9:
     name: Sanity check c-extension module code in default python3 on Rocky9
     runs-on: ubuntu-latest
     container: