Not an error if commit too far away

[tomaka]

This is an amendment to #2400

It is not a problem in the GrandPa commit either if it targets a block too far away. We just save it for later.

[mergify]

Automatically approving tomaka's pull requests. This auto-approval will be removed once more maintainers are active.

[github-actions]

twiggy diff report

Difference in .wasm size before and after this pull request.

---

 Delta Bytes │ Item
─────────────┼────────────────────────────────────────────────────────────────────────────────────────────────
         +14 ┊ smoldot::sync::all_forks::AllForksSync<TBl,TRq,TSrc>::grandpa_commit_message::h16420afe5b974889
         +14 ┊ smoldot::sync::all_forks::FinalityProofVerify<TBl,TRq,TSrc>::perform::h06885296c1832f90
         +28 ┊ Σ [2 Total Rows]