Fix crash when character comments on their tits; ensure self.tits_value is...

I'm sorry, but an uncaught exception occurred.

While running game code:
  File "game/script.rpy", line 254, in script call
    $ talk_action.call_action(picked_option)
  File "game/crises/limited_time_crises/general_LTE.rpy", line 112, in script call
    call talk_person(the_person) from _call_talk_person_10
  File "game/script.rpy", line 408, in script call
    $ _return.call_action(the_person)
  File "game/general_actions/interaction_actions/chat_actions.rpy", line 920, in script call
    call fuck_person(the_person, private = should_be_private, start_position = standing_grope, start_object = None, skip_intro = True) from _call_fuck_person_43 # Enter the sex system, starting from this point.
  File "game/general_actions/interaction_actions/sex_mechanics.rpy", line 203, in script call
    call sex_description(the_person, position_choice, object_choice, private = private, report_log = report_log) from _call_sex_description
  File "game/general_actions/interaction_actions/sex_mechanics.rpy", line 485, in script call
    $ the_position.call_scene(the_person, mc.location, the_object)
  File "game/sex_positions/tit_fuck.rpy", line 77, in script
    the_girl "Mmm, fuck my tits [the_girl.mc_title], they're all yours."
  File "game/major_game_classes/character_related/Person.rpy", line 1477, in __call__
    tit_effect_strength = str(int(6*(self.arousal/self.max_arousal)) + (self.tit_value * 2))
  File "game/major_game_classes/character_related/Person.rpy", line 1526, in __getattr__
    raise AttributeError("No attribute: " + attr)
AttributeError: No attribute: tit_value

-- Full Traceback ------------------------------------------------------------

Full traceback:
  File "game/script.rpy", line 254, in script call
    $ talk_action.call_action(picked_option)
  File "game/crises/limited_time_crises/general_LTE.rpy", line 112, in script call
    call talk_person(the_person) from _call_talk_person_10
  File "game/script.rpy", line 408, in script call
    $ _return.call_action(the_person)
  File "game/general_actions/interaction_actions/chat_actions.rpy", line 920, in script call
    call fuck_person(the_person, private = should_be_private, start_position = standing_grope, start_object = None, skip_intro = True) from _call_fuck_person_43 # Enter the sex system, starting from this point.
  File "game/general_actions/interaction_actions/sex_mechanics.rpy", line 203, in script call
    call sex_description(the_person, position_choice, object_choice, private = private, report_log = report_log) from _call_sex_description
  File "game/general_actions/interaction_actions/sex_mechanics.rpy", line 485, in script call
    $ the_position.call_scene(the_person, mc.location, the_object)
  File "game/sex_positions/tit_fuck.rpy", line 77, in script
    the_girl "Mmm, fuck my tits [the_girl.mc_title], they're all yours."
  File "E:\Games\Blur\Lab_Rats_2-v0.52.0a_2022-12-13\renpy\ast.py", line 921, in execute
    renpy.exports.say(who, what, *args, **kwargs)
  File "E:\Games\Blur\Lab_Rats_2-v0.52.0a_2022-12-13\renpy\exports.py", line 1373, in say
    who(what, *args, **kwargs)
  File "game/major_game_classes/character_related/Person.rpy", line 1477, in __call__
    tit_effect_strength = str(int(6*(self.arousal/self.max_arousal)) + (self.tit_value * 2))
  File "game/major_game_classes/character_related/Person.rpy", line 1526, in __getattr__
    raise AttributeError("No attribute: " + attr)
AttributeError: No attribute: tit_value

Windows-10-10.0.19045 AMD64
Ren'Py 8.0.1.22070801
Lab Rats 2 - Down to Business v0.52.0a_TECH_DEMO
Wed Dec 14 10:26:08 2022