settings: fix visual error when choosing font.

In the settings panel after selecting the font
and then returning to the main settings window,
white artifacts polluted the widget. We need to
delete this object.

src/bin/screens/edi_settings_font.c

@@ -67,6 +67,7 @@ _font_monospaced_check(const char *name, Evas_Object *parent)
 
    evas_object_text_text_set(textblock, "m");
    evas_object_geometry_get(textblock, NULL, NULL, &w2, NULL);
+   evas_object_del(textblock);
 
    // check width difference is small or zero.
    diff = (w2 >= w1) ? w2 - w1 : w1 - w2;