ci(workflows): improve security and update actions

- set top-level explicit permissions for each GitHub Actions workflow for improved security and deduplication of permissions.
- add `persist-credentials: false` to actions/checkout for improved security - see https://github.com/actions/checkout#checkout-v4
- update actions/checkout from v4 to v5

.github/workflows/chore-lock-closed-issues-discussions-and-prs.yml

@@ -4,6 +4,11 @@ on:
   schedule:
     - cron: '0 1 * * *'
 
+permissions:
+  issues: write
+  discussions: write
+  pull-requests: write
+
 jobs:
   lock-threads:
     runs-on: ubuntu-latest
@@ -13,5 +18,5 @@ jobs:
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}
           issue-inactive-days: '30'
-          pr-inactive-days: '30'
           discussion-inactive-days: '30'
+          pr-inactive-days: '30'