Add Python 3.13 to the testing matrix (#597)

* Add Python 3.13 to the testing matrix

* Try to pin a Python3.13-compatible `cffi`

* Add comment about removing pinned `cffi`

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Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>

Author: 3 people

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13"]
 
     steps:
       - uses: actions/checkout@v4

requirements.txt

@@ -2,6 +2,7 @@ aiohttp==3.9.5
 appdirs==1.4.4
 async-timeout==4.0.3
 cachetools==5.3.3
+cffi==v1.17.0rc1 # remove this once v1.17.0 is out
 chardet==5.2.0
 gidgethub==5.3.0
 multidict==6.0.5