Translation italian: multilingual.mdx (#17768)

* added multilingual.mdx

* updated multilingual.mdx

* italian translation multilingual.mdx

* updated _toctree.yml

* fixed typos _toctree.yml

* fixed typos after review

* fixed error after review

docs/source/it/_toctree.yml

@@ -14,3 +14,6 @@
   - local: preprocessing
     title: Preprocess
   title: Esercitazione
+- sections:
+  - local: multilingual
+    title: Modelli multilingua per l'inferenza