migrate to V2 Cargo.lock format

[antiochp]

This PR takes our recently updated Cargo.lock file and translates it to V2 format.

See here for context -
rust-lang/cargo#7070

Tool used for translation -
https://github.com/rustsec/cargo-lock

cargo lock translate > Cargo.lock2
mv Cargo.lock2 Cargo.lock

Cargo.lock in grin-wallet was updated in the recent past to V2 and this PR makes Cargo.lock here consistent with that.

V2 has been supported in cargo for a while now and was recently enabled as the default to be used for new projects. Even relatively old versions of cargo support this new version so we should be perfectly fine to switch over at this point.

tl;dr Cargo.lock V2 format should make merge conflicts far less of an ordeal going forward.

rust-lang/cargo#7070

This commit is an attempt to refine Cargo's lock file format to generate
less git merge conflicts for lock file updates as well as make it easier
to manage lock file updates. The new lock file format has a few major changes:

The [metadata] table is no longer used to track checksums. The
packages themselves now list checksum fields directly.

The entries in the dependencies key no longer unconditionally
mention the version/source of the dependency. When unambiguous only
the name or only the name/version are mentioned.

[quentinlesceller]

Nice! Totally missed out that v1 and v2 Cargo.lock thing.

[antiochp]

Nice! Totally missed out that v1 and v2 Cargo.lock thing.

I think this is a good time to do this, given we recently updated the dependencies themselves.