help: Use new attack stats separator in unit descriptions

Closes #2873.

(This is part of a commented-out block in master because Vultraz hasn't
updated the code yet. He said I could forward-port the patch into it
anyway. For the time being unit descriptions are just completely missing
because of this.)

(cherry-picked from commit 7f8cb13bd3)

changelog.md

@@ -10,6 +10,9 @@
      * S12 Fixed north treasure chest disappearing
    * Under the Burning Suns
      * Hide technical terrains in the Help browser (Human Ship, Lava overlay).
+ ### Help browser
+   * Unit descriptions use the new multiplication sign format for attack lists
+     now (issue #2873).
  ### Language and i18n
    * Fixed many cases of interpolated strings in the engine possibly having
      their translations retrieved from the wrong textdomain and falling back

src/help/help_topic_generators.cpp

@@ -524,7 +524,7 @@ std::string unit_topic_generator::operator()() const {
 			push_tab_pair(row, lang_weapon);
 			push_tab_pair(row, lang_type);
 			attack_ss.str(clear_stringstream);
-			attack_ss << attack.damage() << font::unicode_en_dash << attack.num_attacks()
+			attack_ss << attack.damage() << font::weapon_numbers_sep << attack.num_attacks()
 				<< " " << attack.accuracy_parry_description();
 			push_tab_pair(row, attack_ss.str());
 			attack_ss.str(clear_stringstream);