Change the link destination of cargo book contribution

`src/doc` directory has `README.md` about Cargo documentation including description for contribution, while `src/doc/src` does not have such a document.
rust-lang · Dec 4, 2019 · 0d32d5b · 0d32d5b
1 parent 6b4dd23
commit 0d32d5b
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/doc/src/index.md b/src/doc/src/index.md
@@ -27,4 +27,4 @@ The reference covers the details of various areas of Cargo.
 
 [rust]: https://www.rust-lang.org/
 [crates.io]: https://crates.io/
-[GitHub]: https://github.com/rust-lang/cargo/tree/master/src/doc/src
+[GitHub]: https://github.com/rust-lang/cargo/tree/master/src/doc