Log Message:
security/gpg-tui: update to 0.8.2

Changed
Allow showing options menu for empty keyrings
Update the edition of Rust to 2021
Copy Cargo.lock into docker build stage for caching
Bump the Rust version in Dockerfile
Use ubuntu-20.04 runner for workflows
Specify the toolchain explicitly for crates.io releases
Install Rust toolchain for audit job
Apply clippy::format_in_format_args suggestion
Apply clippy::single_char_pattern suggestion

Fixed
Fix config file extension in README.md
Use references for OS command arguments
Fix the Rust profile specification in audit workflow