Fix untranslated string

Closes #8809.

src/gui/properties/peersadditiondlg.cpp

@@ -39,9 +39,6 @@ PeersAdditionDlg::PeersAdditionDlg(QWidget *parent)
 {
     m_ui->setupUi(this);
     connect(m_ui->buttonBox, SIGNAL(accepted()), this, SLOT(validateInput()));
-
-    m_ui->label_format->hide();
-    m_ui->peers_txt->setPlaceholderText("Format: IPv4:port / [IPv6]:port");
 }
 
 PeersAdditionDlg::~PeersAdditionDlg()

src/gui/properties/peersadditiondlg.ui

@@ -29,11 +29,7 @@
      <property name="acceptRichText">
       <bool>false</bool>
      </property>
-    </widget>
-   </item>
-   <item>
-    <widget class="QLabel" name="label_format">
-     <property name="text">
+     <property name="placeholderText">
       <string>Format: IPv4:port / [IPv6]:port</string>
      </property>
     </widget>