tv: select first item after toggling deletion mode

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

ui/src/main/java/com/wireguard/android/activity/TvMainActivity.kt

@@ -120,6 +120,9 @@ class TvMainActivity : AppCompatActivity() {
         }
         binding.deleteButton.setOnClickListener {
             isDeleting.set(!isDeleting.get())
+            runOnUiThread {
+                binding.tunnelList.requestFocus()
+            }
         }
         binding.executePendingBindings()
         setContentView(binding.root)