Add current available Python & PyPY versions to CI tests

Author: eemeli

.github/workflows/ci.yml

@@ -13,7 +13,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
-          python-version: 3.9
+          python-version: 3.12
       - run: python -m pip install -r dev-requirements.txt
       - run: python -m pip install ./fluent.syntax ./fluent.runtime
       - run: python -m flake8
@@ -22,7 +22,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.7, 3.8, 3.9, pypy3.9]
+        python-version: [3.7, 3.8, 3.9, "3.10", 3.11, 3.12, pypy3.9, pypy3.10]
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5