Update Cargo.lock

[orhun]

Describe the bug
Using --locked flag with cargo build fails because Cargo.lock is not up-to-date.

error: Cargo.lock needs to be updated but --locked was passed to prevent this
If you want to try to generate the lock file without accessing the network, use the --offline flag.

Usage of --locked flag is important for the AUR package's reproducibility.

(I also recommend you to release a new version after updating the Cargo.lock file)

To Reproduce

1. Checkout the repository.
2. Run any cargo command with --locked flag. (e.g. cargo build --locked)

Expected behavior
Successful build.

System Info

• OS: Arch Linux
• Rust: 1.50.0-nightly

Additional context
You should update the Cargo.lock file for solving this issue. Please use cargo build command and commit the updated Cargo.lock file.