Add CPython 3.13 and PyPy 3.11 to versions on CI (#268)

Author: davidparsson

.github/workflows/ci.yml

@@ -1,6 +1,6 @@
 name: CI
 
-on: 
+on:
   push:
     branches:
       - master
@@ -12,7 +12,19 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        python-version: [3.8, 3.9, "3.10", "3.11", "3.12", "pypy3.8", "pypy3.9", "pypy3.10"]
+        python-version:
+          [
+            3.8,
+            3.9,
+            "3.10",
+            "3.11",
+            "3.12",
+            "3.13",
+            "pypy3.8",
+            "pypy3.9",
+            "pypy3.10",
+            "pypy3.11",
+          ]
     steps:
     - uses: actions/checkout@v2
     - name: Set up Python ${{ matrix.python-version }}