Pin sphinx version

Author: Starbuck5

.github/workflows/build.yml

@@ -41,7 +41,7 @@ jobs:
       - name: Generate the pygame-ce documentation
         run: |
           python -m pip install --upgrade pip
-          pip install sphinx
+          pip install sphinx==7.1.2
           git clone https://github.com/pygame-community/pygame-ce.git
           cd pygame-ce
           python setup.py docs