Temporarily pin to 3.12.0a4 pending dependency support for a5+ (#331)

Author: hugovk

.github/workflows/ci.yml

@@ -12,7 +12,10 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12-dev"]
+        # TODO replace 3.12.0-alpha.4 with 3.12-dev when
+        # aiohttp, frozenlist and yarl support alpha 5+
+        # https://github.com/python/blurb_it/pull/330#issuecomment-1449496275
+        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12.0-alpha.4"]
 
     steps:
       - uses: actions/checkout@v3