Replace broken link about source-based-coverage

This content seems to have been removed from the unstable book because
it's in the process of stabilizing.

posts/inside-rust/2020-11-12-source-based-code-coverage.md

@@ -60,16 +60,18 @@ Work on the implementation [began back in April][MCP], and [many PRs
 later][PRs], it’s ready for you to try. All you need is a recent nightly and
 a tool to read the coverage reports.
 
-[Take a look at this guide to get started][guide]. If you spot any issues,
-please [report them]. It’s a huge help!
+The easiest way to get stared with source-based coverage is through 
+[`cargo-llvm-cov`][cargo-llvm-cov].
+
+If you spot any issues, please [report them]. It’s a huge help!
 
 Finally, if you try it out and it works well, we’d also like to hear from
 you! Come by the [Zulip stream] for this change or comment on the [feature
 request].
 
 [MCP]: https://github.com/rust-lang/compiler-team/issues/278
 [PRs]: https://github.com/rust-lang/rust/pulls?q=is%3Apr+author%3Arichkadel+is%3Aclosed+closed%3A%3C2020-11-06
-[guide]: https://doc.rust-lang.org/nightly/unstable-book/compiler-flags/source-based-code-coverage.html
+[cargo-llvm-cov]: https://github.com/taiki-e/cargo-llvm-cov
 [report them]: https://github.com/rust-lang/rust/issues/new/choose
 [Zulip stream]: https://rust-lang.zulipchat.com/#narrow/stream/233931-t-compiler.2Fmajor-changes/topic/Implement.20LLVM-compatible.20source-based.20cod.20compiler-team.23278
 [feature request]: https://github.com/rust-lang/rust/issues/34701