translationBot(ui): update translation (Italian)

Currently translated at 99.3% (1578 of 1588 strings)

Co-authored-by: Riccardo Giovanetti <[email protected]>
Translate-URL: https://hosted.weblate.org/projects/invokeai/web-ui/it/
Translation: InvokeAI/Web UI

Author: Harvester62

invokeai/frontend/web/public/locales/it.json

@@ -95,7 +95,8 @@
         "close": "Chiudi",
         "clipboard": "Appunti",
         "ok": "Ok",
-        "generating": "Generazione"
+        "generating": "Generazione",
+        "loadingModel": "Caricamento del modello"
     },
     "gallery": {
         "galleryImageSize": "Dimensione dell'immagine",