gnu: rust-rustc-test-0.3: Correct cargo-inputs.

* gnu/packages/crates-io.scm (rust-rustc-test-0.3)[arguments]: Replace
rust-term-0.5 with 0.4 in cargo-inputs. Move rust-rustc-version-0.2 from
cargo-development-inputs to cargo-inputs.

Signed-off-by: Efraim Flashner <efraim@flashner.co.il>