fix: remove the reset-to-defaults button from tag settings

If you carefully crafted your tags and then click this button by accident, all
your hard work is gone. A confirmation message would be the other solution but
since I have difficulty to grasp when you would need such a button, I propose
to just remove it.

locales/it/common.json

@@ -1016,7 +1016,6 @@
       "title": "Etichette e-mail",
       "description": "Definisci etichette per organizzare le tue e-mail con i colori. Vengono archiviate come parole chiave JMAP sul server.",
       "add_keyword": "Aggiungi etichetta",
-      "reset_defaults": "Ripristina predefiniti",
       "label_field": "Nome visualizzato",
       "label_placeholder": "es. Lavoro, Personale, Urgente",
       "id_field": "ID etichetta",