Add event.Skip() call so someone else handles the focus.

DIALOG_EDIT_ONE_FIELD::OnSetFocusText() is only for setting the
selection correctly, not doing the actual focus.

Fixes: lp:1783615
* https://bugs.launchpad.net/kicad/+bug/1783615

eeschema/dialogs/dialog_edit_one_field.cpp

@@ -181,6 +181,8 @@ void DIALOG_EDIT_ONE_FIELD::OnSetFocusText( wxFocusEvent& event )
     {
         m_TextValue->SetSelection( -1, -1 );
     }
+
+    event.Skip();
 }