chore(deps): update actions/stale action to v8

Author: renovate[bot]

.github/workflows/prune.yaml

@@ -18,7 +18,7 @@ jobs:
 
         steps:
             - name: "Prune issues and pull requests"
-              uses: "actions/stale@v7"
+              uses: "actions/stale@v8"
               with:
                   days-before-close: "${{ env.DAYS_BEFORE_CLOSE }}"
                   days-before-stale: "${{ env.DAYS_BEFORE_STALE }}"