update the idna dep (and url, hickory-proto)

[leighmcculloch]

What

Update the idna dep, and update transitive deps accordingly, as well as the url and hickory-proto deps to be able to use the newer idna.

Why

The idna crate that the url and hickory-proto crate depend on has a rust security alert seen in the cargo-deny runs:

• https://github.com/stellar/stellar-cli/actions/runs/12272048746/job/34240032844

Commands run for anyone wishing to verify / replicate:

$ cargo update -p url
$ cargo update -p hickory-proto

[leighmcculloch]

Pending question with legal regarding the Unicode-3.0 license error:

• https://github.com/stellar/stellar-cli/actions/runs/12272928140/job/34242704350

[leighmcculloch]

Unicode 3.0 was approved, but this PR is dependent on embedding the licenses in the software, i.e.:

• Add stellar licenses to display all dependencies' licenses #1837

[leighmcculloch]

Oops, I had meant to merge this after #1837. We need to make sure we don't release the stellar-cli with this change until #1837 is merged.