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/ar/common.json

@@ -1019,7 +1019,6 @@
       "title": "وسوم البريد",
       "description": "عرّف وسومًا لتنظيم رسائلك بالألوان. تُخزَّن هذه ككلمات مفتاحية JMAP على الخادم.",
       "add_keyword": "إضافة وسم",
-      "reset_defaults": "إعادة التعيين للافتراضي",
       "label_field": "الاسم المعروض",
       "label_placeholder": "مثال: عمل، شخصي، عاجل",
       "id_field": "معرّف الوسم",