gui2/unit_create: Do not exclude do_not_list units

This is a debug mode-only dialog. If I want to spawn a unit, the game
had better allow me to spawn any unit I want. do_not_list was created
for use by wmlunits anyway.

(cherry-picked from commit 085236f556)

changelog.md

@@ -234,6 +234,8 @@
      matching 1.12's behavior again.
    * [message] displays the unit type name when a nameless unit speaks and no
      custom caption= is specified (fixes #3211).
+   * do_not_list=yes units are no longer excluded from the debug mode-only
+     Create Unit dialog.
 
 ## Version 1.13.12
  ### Security fixes

src/gui/dialogs/unit_create.cpp

@@ -118,9 +118,6 @@ void unit_create::pre_show(window& window)
 
 	for(const auto & i : unit_types.types())
 	{
-		if(i.second.do_not_list())
-			continue;
-
 		// Make sure this unit type is built with the data we need.
 		unit_types.build_unit_type(i.second, unit_type::FULL);