Test 6.x branch on python 3.14 and 3.14t

Author: ianthomas23

.github/workflows/ci.yml

@@ -28,6 +28,8 @@ jobs:
           - "3.11"
           - "3.12"
           - "3.13"
+          - "3.14"
+          - "3.14t"
           - "pypy-3.10"
     steps:
       - name: Checkout