ci(code-formatting-check): grant actions:write on taplo-fmt for cache

Per Copilot review on #657: `taiki-e/cache-cargo-install-action` writes to the GitHub Actions cache. With the workflow's default permissions pinned to `contents: read`, that step would fail without an `actions: write` scope on the `taplo-fmt` job. Adds a per-job permissions block so the cache save/restore continues to work after the workflow-level restriction.

Signed-off-by: Arpit Jain <arpitjain099@gmail.com>

Author: arpitjain099

.github/workflows/code-formatting-check.yaml

@@ -36,6 +36,9 @@ jobs:
   taplo-fmt:
     name: .toml Formatting Check
     runs-on: windows-2025
+    permissions:
+      contents: read
+      actions: write # taiki-e/cache-cargo-install-action writes to GitHub Actions cache
 
     steps:
       - name: Checkout Repository