docs: correct some grammar (#574)

sato11 · web-flow · commit 6278efebb38a · 2024-01-11T00:31:20.000+11:00
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
@@ -1,7 +1,7 @@
 # Contributing
 
 [asdf](https://asdf-vm.com) is used to manage the development tools for these
-GitHub Actions. See it's documentation to install and setup on your machine.
+GitHub Actions. See its documentation to install and setup on your machine.
 
 ## Setup
 
