test-macro: Add Cargo.toml metadata

Author: fitzgen

crates/test-macro/Cargo.toml

@@ -2,6 +2,9 @@
 name = "wasm-bindgen-test-macro"
 version = "0.2.15"
 authors = ["The wasm-bindgen Developers"]
+description = "Internal testing macro for wasm-bindgen"
+license = "MIT/Apache-2.0"
+repository = "https://github.com/rustwasm/wasm-bindgen"
 
 [dependencies]
 proc-macro2 = { version = "0.4", features = ['nightly'] }