Fix typo

Author: eregon

README.md

@@ -4,7 +4,7 @@
   <a href="https://github.com/actions/setup-ruby"><img alt="GitHub Actions status" src="https://github.com/actions/setup-ruby/workflows/Main%20workflow/badge.svg"></a>
 </p>
 
-This action sets up a ruby environment for versions which are installed on the [Actions Virtual Environments](https://github.com/actions/virtual-environments).  Because virtual environments are updated, a workflow should only be bound to a minor versions.  
+This action sets up a ruby environment for versions which are installed on the [Actions Virtual Environments](https://github.com/actions/virtual-environments).  Because virtual environments are updated, a workflow should only be bound to a minor version.  
 
 > Only supports `2.4.x`, `2.5.x`, and `2.6.x`.