[BUG] Fix rare ArgumentOutOfRangeException TextBoxSearch_TextChanged

[Hofknecht]

System.ArgumentOutOfRangeException: Specified argument was out of the
range of valid values. (Parameter 'value') at
System.Windows.Forms.DataGridView.set_FirstDisplayedScrollingRowIndex(Int32
value) at
SystemTrayMenu.UserInterface.Menu.TextBoxSearch_TextChanged(Object
sender, EventArgs e) in
D:\Seafile\Markus\C#Projects\systemtraymenu\UserInterface\Menu.cs:line
891 at System.Windows.Forms.Control.OnTextChanged(EventArgs e) at
System.Windows.Forms.TextBoxBase.OnTextChanged(EventArgs e) at
System.Windows.Forms.Control.set_Text(String value) at
System.Windows.Forms.TextBoxBase.set_Text(String value) at
System.Windows.Forms.TextBox.set_Text(String value) at
SystemTrayMenu.UserInterface.Menu.ResetSearchText() in
D:\Seafile\Markus\C#Projects\systemtraymenu\UserInterface\Menu.cs:line
232 at
SystemTrayMenu.Business.Menus.<.ctor>g__LoadMainMenuCompleted|21_0(Object
sender, RunWorkerCompletedEventArgs e) in
D:\Seafile\Markus\C#Projects\systemtraymenu\Business\Menus.cs:line 81 at
System.ComponentModel.BackgroundWorker.OnRunWorkerCompleted(RunWorkerCompletedEventArgs
e) at
System.ComponentModel.BackgroundWorker.AsyncOperationCompleted(Object arg)