docs: fix a few links

Author: calebcartwright

CHANGELOG.md

@@ -10,7 +10,7 @@
 - Support for formatting let-else statements [#5690]
 - New config option, `single_line_let_else_max_width`, that allows users to configure the maximum length of single line `let-else` statements. `let-else` statements that otherwise meet the requirements to be formatted on a single line will have their divergent`else` block formatted over multiple lines if they exceed this length [#5684]
 
-[#5690]: (https://github.com/rust-lang/rustfmt/pulls/5690)
+[#5690]: https://github.com/rust-lang/rustfmt/pulls/5690
 [#5684]: https://github.com/rust-lang/rustfmt/issues/5684
 
 ## [1.5.3] 2023-06-20

README.md

@@ -229,4 +229,4 @@ See [LICENSE-APACHE](LICENSE-APACHE) and [LICENSE-MIT](LICENSE-MIT) for details.
 
 [rust]: https://github.com/rust-lang/rust
 [fmt rfcs]: https://github.com/rust-dev-tools/fmt-rfcs
-[style guide]: https://github.com/rust-dev-tools/fmt-rfcs/blob/master/guide/guide.md
+[style guide]: https://doc.rust-lang.org/nightly/style-guide/