Codechange: Replace FOR_ALL_CARGOSPECS with range-based for loops

(cherry picked from commit 9a8756d7ed)

src/town_cmd.cpp

@@ -3102,8 +3102,7 @@ CommandCost CmdRenameTownNonAdmin(TileIndex tile, DoCommandFlag flags, uint32 p1
  */
 const CargoSpec *FindFirstCargoWithTownEffect(TownEffect effect)
 {
-	const CargoSpec *cs;
-	FOR_ALL_CARGOSPECS(cs) {
+	for (const CargoSpec *cs : CargoSpec::Iterate()) {
 		if (cs->town_effect == effect) return cs;
 	}
 	return nullptr;