Abandon camp fix (#37976)

* use different pos as random NPC can be invalidated

* remove random guy

src/faction_camp.cpp

@@ -1557,21 +1557,19 @@ void basecamp::start_upgrade( const std::string &bldg, const point &dir,
 void basecamp::abandon_camp()
 {
     validate_assignees();
-    npc_ptr random_guy;
     for( npc_ptr &guy : overmap_buffer.get_companion_mission_npcs( 10 ) ) {
         npc_companion_mission c_mission = guy->get_companion_mission();
         if( c_mission.role_id != base_camps::id ) {
             continue;
         }
-        random_guy = guy;
         const std::string return_msg = _( "responds to the emergency recall…" );
         finish_return( *guy, false, return_msg, "menial", 0, true );
     }
     for( npc_ptr &guy : get_npcs_assigned() ) {
         talk_function::stop_guard( *guy );
     }
     overmap_buffer.remove_camp( *this );
-    g->m.remove_submap_camp( random_guy->pos() );
+    g->m.remove_submap_camp( bb_pos );
     add_msg( m_info, _( "You abandon %s." ), name );
 }