Fix broken link to Rust FAQ

It seems the Rust FAQ was dropped with website redesign. This question doesn't seem to be answered on any current resource, but the old website is still available.

Also updated link to Code of Conduct.

Author: intgr

CONTRIBUTING.md

@@ -89,4 +89,4 @@ As with all Rust-related spaces, we observe the [Rust Code of Conduct]. For
 escalation or moderation issues please contact the Rust moderation team,
 [email protected].
 
-[Rust Code of Conduct]: https://www.rust-lang.org/conduct.html
+[Rust Code of Conduct]: https://www.rust-lang.org/policies/code-of-conduct

src/necessities.md

@@ -56,7 +56,7 @@ over licensing options.
 
 [MIT]: https://github.com/rust-lang/rust/blob/master/LICENSE-MIT
 [Apache 2.0]: https://github.com/rust-lang/rust/blob/master/LICENSE-APACHE
-[Rust FAQ]: https://www.rust-lang.org/en-US/faq.html#why-a-dual-mit-asl2-license
+[Rust FAQ]: https://prev.rust-lang.org/en-US/faq.html#why-a-dual-mit-asl2-license
 
 To apply the Rust license to your project, define the `license` field in your
 `Cargo.toml` as: