chore: migrate bump-version workflow to PAT_GITHUB and checkout v6

Author: mfazekas

.github/workflows/bump-version.yml

@@ -22,9 +22,9 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out source
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
-          token: ${{ secrets.GITHUB_TOKEN }}
+          token: ${{ secrets.PAT_GITHUB }}
 
       - name: Setup Node.js
         uses: actions/setup-node@v4