ci(nightly): spec-5.18 extend stage5 shard range 276-324 -> 276-325

Include the new t/325 (spec-5.18 permanent node-removal 2-node e2e) in the
nightly Linux stage5-ges-locking shard so the removal e2e runs in CI.

Author: SqlRush

.github/workflows/nightly.yml

@@ -149,7 +149,7 @@ jobs:
           - { name: stage3-recent,     ranges: "228-237", unit: false, regress: false }
           - { name: stage4-wal,        ranges: "242-248 273 275", unit: false, regress: false }
           - { name: stage4-hardgate,   ranges: "274-274", unit: false, regress: false }
-          - { name: stage5-ges-locking, ranges: "276-324", unit: false, regress: false }
+          - { name: stage5-ges-locking, ranges: "276-325", unit: false, regress: false }
     steps:
       - name: Checkout
         uses: actions/checkout@v4