Fix typo in 7th line

Co-authored-by: Brian Cristante <33549821+brcrista@users.noreply.github.com>

README.md

@@ -4,7 +4,7 @@
   <a href="https://github.com/actions/setup-python"><img alt="GitHub Actions status" src="https://github.com/actions/setup-python/workflows/Main%20workflow/badge.svg"></a>
 </p>
 
-This action provides the following functionalities for GitHub Actions users:
+This action provides the following functionality for GitHub Actions users:
 
 - Optionally installing and adding to PATH a version of Python that is already installed in the runner's tool cache.
 - Downloading, installing and adding to PATH an available version of Python from GitHub Releases ([actions/python-versions](https://github.com/actions/python-versions/releases)) if a specific version is not available in the runner's tool cache.