Fix ArrayIndexOutOfBoundsException (#3808)

Fixes https://github.com/tuskyapp/Tusky/issues/3807

app/src/main/java/com/keylesspalace/tusky/adapter/AccountFieldEditAdapter.kt

@@ -82,11 +82,11 @@ class AccountFieldEditAdapter : RecyclerView.Adapter<BindingHolder<ItemEditField
         }
 
         holder.binding.accountFieldNameText.doAfterTextChanged { newText ->
-            fieldData[holder.bindingAdapterPosition].first = newText.toString()
+            fieldData.getOrNull(holder.bindingAdapterPosition)?.first = newText.toString()
         }
 
         holder.binding.accountFieldValueText.doAfterTextChanged { newText ->
-            fieldData[holder.bindingAdapterPosition].second = newText.toString()
+            fieldData.getOrNull(holder.bindingAdapterPosition)?.second = newText.toString()
         }
 
         // Ensure the textview contents are selectable