0.5.4

• Use cargo-config2 to load Cargo configuration. (#237)

  This brings the following improvements:

  • More accurate cargo configuration loading and resolution.
  • Fix installation failure on Rust 1.60 and 1.61 by removing dependency on target-spec.
  • Remove run-time dependency on unstable cargo config get. (Previously, this command was used in a form allowing failure, like rust-analyzer does.)