EASE_IN no longer required for interpolate_property (#3589)

* EASE_IN no longer required for interpolate_property in Control the game's UI with code

Was fixed here godotengine/godot#34287

* Update ui_code_a_life_bar.rst

Missed a spot.

* TRANS_LINEAR is optional. Remove it as well

getting_started/step_by_step/ui_code_a_life_bar.rst

@@ -405,7 +405,7 @@ clear its content. Let's animate the ``animated_health`` value. Call the
  .. code-tab:: gdscript GDScript
 
     func update_health(new_value):
-        tween.interpolate_property(self, "animated_health", animated_health, new_value, 0.6, Tween.TRANS_LINEAR, Tween.EASE_IN)
+        tween.interpolate_property(self, "animated_health", animated_health, new_value, 0.6)
 
  .. code-tab:: csharp
 
@@ -438,15 +438,6 @@ of the animation is the ``Player``'s ``health`` after the
 ``health_changed``: that's ``new_value``. And ``0.6`` is the animation's
 duration in seconds.
 
-::
-
-    ...  0.6, Tween.TRANS_LINEAR, Tween.EASE_IN)
-
-The last two arguments are constants from the ``Tween`` class.
-``TRANS_LINEAR`` means the animation should be linear. ``EASE_IN``
-doesn't do anything with a linear transition, but we must provide this
-last argument or we'll get an error.
-
 The animation will not play until we activated the ``Tween`` node with
 ``tween.start()``. We only have to do this once if the node is not
 active. Add this code after the last line:
@@ -480,7 +471,7 @@ So far, the update\_health method looks like this:
  .. code-tab:: gdscript GDScript
 
     func update_health(new_value):
-        tween.interpolate_property(self, "animated_health", animated_health, new_value, 0.6, Tween.TRANS_LINEAR, Tween.EASE_IN)
+        tween.interpolate_property(self, "animated_health", animated_health, new_value, 0.6)
         if not tween.is_active():
             tween.start()
 
@@ -644,7 +635,7 @@ We then have to call the ``interpolate_property`` method of the
 .. tabs::
  .. code-tab:: gdscript GDScript
 
-    tween.interpolate_property(self, "modulate", start_color, end_color, 1.0, Tween.TRANS_LINEAR, Tween.EASE_IN)
+    tween.interpolate_property(self, "modulate", start_color, end_color, 1.0)
 
  .. code-tab:: csharp
 
@@ -653,8 +644,7 @@ We then have to call the ``interpolate_property`` method of the
 
 This time, we change the ``modulate`` property and have it animate from
 ``start_color`` to the ``end_color``. The duration is of one second,
-with a linear transition. Here again, because the transition is linear,
-the easing does not matter. Here's the complete ``_on_Player_died``
+with a linear transition. Here's the complete ``_on_Player_died``
 method:
 
 .. tabs::
@@ -663,7 +653,7 @@ method:
     func _on_Player_died():
         var start_color = Color(1.0, 1.0, 1.0, 1.0)
         var end_color = Color(1.0, 1.0, 1.0, 0.0)
-        tween.interpolate_property(self, "modulate", start_color, end_color, 1.0, Tween.TRANS_LINEAR, Tween.EASE_IN)
+        tween.interpolate_property(self, "modulate", start_color, end_color, 1.0)
 
  .. code-tab:: csharp