fix(courses): deleted broken link (#6893)

courses/free-courses-it.md

@@ -79,7 +79,6 @@
 
 ### Database
 
-* [Basi di dati](https://www.youtube.com/playlist?list=PLgaOrAQwrg9JZs6dbDolNlShHFgpJSChj) (M. De Ghetto)
 * [Basi di Dati](https://www.youtube.com/playlist?list=PLAQopGWlIcyZ7CN1sefdnCusfoodLP931) (T. Catarci)