Update base-documentation.md, fix CONTRIBUTING spelling (InnerSourceCommons#552)

Author: jeffabailey

patterns/2-structured/project-setup/base-documentation.md

@@ -109,7 +109,7 @@ started right away: [README-template.md](templates/README-template.md) and
 
 * Europace AG - See blog post [InnerSource: Adding base documentation](https://tech.europace.de/post/innersource-base-documentation/)
 * Paypal Inc.
-* Mercado Libre - create a documentation site that contains how to get started with InnerSource and also define the basic artifacts that a repository must have to be InnerSource (README, CONTRIBNUTING, CODING_GUIDELINES, etc).
+* Mercado Libre - create a documentation site that contains how to get started with InnerSource and also define the basic artifacts that a repository must have to be InnerSource (README, CONTRIBUTING, CODING_GUIDELINES, etc).
 
 ## Authors