chore(deps): update fvm_ipld_amt requirement from 0.6.1 to 0.7.1

Updates the requirements on [fvm_ipld_amt](https://github.com/filecoin-project/ref-fvm) to permit the latest version.
- [Changelog](https://github.com/filecoin-project/ref-fvm/blob/master/doc/testnet-release-process.md)
- [Commits](https://github.com/filecoin-project/ref-fvm/commits)

---
updated-dependencies:
- dependency-name: fvm_ipld_amt
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Cargo.toml

@@ -43,7 +43,7 @@ cid = { version = "0.10", default-features = false, features = ["std"] }
 frc42_dispatch = "7.0.0"
 frc42_macros = "5"
 frc46_token = "11"
-fvm_ipld_amt = "0.6.1"
+fvm_ipld_amt = "0.7.1"
 fvm_ipld_bitfield = "0.6"
 fvm_ipld_blockstore = "0.2"
 fvm_ipld_encoding = "0.4"