Added git to free-programming-books-langs.md (#6160)

Author: Klaudia2432

Diff for: books/free-programming-books-langs.md

@@ -774,6 +774,7 @@ That section got so big, we decided to split it into its own file, the [BY SUBJE
 * [Git Pocket Guide](https://www.oreilly.com/library/view/git-pocket-guide/9781449327507) - Richard E. Silverman
 * [Git Reference](https://web.archive.org/web/20170602211147/http://gitref.org/)
 * [Git Succinctly, Syncfusion](https://www.syncfusion.com/resources/techportal/ebooks/git) (PDF, Kindle) (email address *requested*, not required)
+* [Git-Tutorial For-Beginners](https://product.hubspot.com/blog/git-and-github-tutorial-for-beginners) - HubSpot Product Team 
 * [Git Workflows](http://documentup.com/skwp/git-workflows-book)
 * [Happy Git and GitHub for the useR](https://happygitwithr.com) - Jenny Bryan
 * [How to Collaborate on Github](https://github.com/eonist/How-to-collaborate-on-github) - André J