book: Use cargo add command

Rather than showing exact dependencies in `Cargo.toml`, use the `cargo add`
command. That removes a small step of the release process.

Author: nicholasbishop

PUBLISHING.md

@@ -46,8 +46,7 @@ you will also have to update the corresponding `Cargo.toml` of `uefi` to be:
 uefi-macros = "0.6.0"
 ```
 
-The dependencies in `template/Cargo.toml` and `book/src/tutorial/app.md` should
-also be updated to the new version.
+The dependencies in `template/Cargo.toml` should also be updated to the new version.
 
 [cargo-semver]: https://doc.rust-lang.org/cargo/reference/semver.html
 [semver]: https://semver.org/

book/src/tutorial/app.md

@@ -13,13 +13,10 @@ cargo new my-uefi-app
 cd my-uefi-app
 ```
 
-In `cargo.toml`, add a few dependencies:
+Add a few dependencies:
 
-```toml
-[dependencies]
-log = "0.4"
-uefi = "0.25"
-uefi-services = "0.22"
+```sh
+cargo add log uefi uefi-services
 ```
 
 Replace the contents of `src/main.rs` with this: