ci: bump lock-threads to v6 to fix token validation failure (#4658)

* ci: bump lock-threads to v6 to fix token validation failure

* chore: trigger CLA check re-run (signature already on file since 2026-09-25)

* chore: retrigger CLA status after re-linking the signed account

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Co-authored-by: 金豆 <jindou@jindoudeMacBook-Air.local>
Co-authored-by: Jimmy Bogard <jimmy.bogard@gmail.com>

Author: 3 people

.github/workflows/lock.yml

@@ -16,7 +16,7 @@ jobs:
       discussions: write  # for dessant/lock-threads to lock discussions
     runs-on: ubuntu-latest
     steps:
-      - uses: dessant/lock-threads@v5
+      - uses: dessant/lock-threads@v6
         with:
           issue-inactive-days: 31
           pr-inactive-days: 31