fix(rpc): implement Filecoin.StateGetAllocations

[hanabi1224]

Summary of changes

Changes introduced in this pull request:

• implement RPC method Filecoin.StateGetAllocations
• API compare tests
• Fix API compare tests for Filecoin.StateGetAllocation

     Running `target/quick/forest-tool api compare /home/me/fr/snapshots/calibnet/forest_snapshot_calibnet_2024-06-05_height_1675679.forest.car.zst --filter StateGetAllocation`
| RPC Method                         | Forest | Lotus |
|------------------------------------|--------|-------|
| Filecoin.StateGetAllocation (381)  | Valid  | Valid |
| Filecoin.StateGetAllocations (108) | Valid  | Valid |

Reference issue to close (if applicable)

Closes https://github.com/ChainSafe/forest/issues/4394 Closes https://github.com/ChainSafe/forest/issues/4386

Other information and links

Change checklist

• [x] I have performed a self-review of my own code,
• [x] I have made corresponding changes to the documentation,
• [x] I have added tests that prove my fix is effective or that my feature works (if possible),
• [x] I have made sure the CHANGELOG is up-to-date. All user-facing changes should be reflected in this document.