actions: build docs on Ubuntu 24.04

Sphinx 3.2 requires Python 3.11+.

.github/workflows/build-docs.yml

@@ -15,7 +15,7 @@ permissions:
 jobs:
   build-documentation:
     name: docs
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-24.04
     steps:
       - uses: actions/checkout@v4
       - name: Install Dependencies