docs: fix cac's dot notation reference link (#3049)

Author: azrikahar

docs/guide/cli.md

@@ -149,3 +149,5 @@ vitest --api=false
 :::warning
 You cannot use this option with `--watch` enabled (enabled in dev by default).
 :::
+
+[cac's dot notation]: https://github.com/cacjs/cac#dot-nested-options

docs/guide/index.md

@@ -138,5 +138,3 @@ Then go to the project where you are using Vitest and run `pnpm link --global vi
 ## Community
 
 If you have questions or need help, reach out to the community at [Discord](https://chat.vitest.dev) and [GitHub Discussions](https://github.com/vitest-dev/vitest/discussions).
-
-[cac's dot notation]: https://github.com/cacjs/cac#dot-nested-options