drop 3.8; upgrade locked deps

Author: simon-weber

.github/workflows/ci.yaml

@@ -11,7 +11,7 @@ jobs:
     name: Pre-commit
     strategy:
       matrix:
-        python-version: [3.8, 3.9]
+        python-version: [3.9] # [3.9, 3.10, 3.11, 3.12, 3.13]
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repository

.python-version

@@ -0,0 +1 @@
+3.9.20