Run release process using Python 3.12

.github/actions/release-initialise/action.yml

@@ -18,12 +18,12 @@ runs:
     - name: Set up Python
       uses: actions/setup-python@v5
       with:
-        python-version: 3.8
+        python-version: 3.12
 
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install PyGithub==1.55 requests
+        pip install PyGithub==2.3.0 requests
       shell: bash
 
     - name: Update git config