feat(AccountSwitcher): add missing empty view holder

Author: zt64

plugin/AccountSwitcher/src/main/kotlin/accountswitcher/settings/EmptyViewHolder.kt

@@ -0,0 +1,19 @@
+package accountswitcher.settings
+
+import android.content.Context
+import android.view.Gravity
+import android.widget.TextView
+import androidx.recyclerview.widget.RecyclerView
+import com.aliucord.utils.DimenUtils
+import com.lytefast.flexinput.R
+
+class EmptyViewHolder(ctx: Context) :
+    RecyclerView.ViewHolder(
+        TextView(ctx, null, 0, R.i.UiKit_TextView_Medium).apply {
+            text = "No accounts have been added."
+            textSize = 16f
+            gravity = Gravity.CENTER
+            val p = DimenUtils.dpToPx(16)
+            setPadding(p, p, p, p)
+        }
+    )