fix type hint of indication.py (#3613)

Author: yuan-xy

manim/animation/indication.py

@@ -148,7 +148,7 @@ def construct(self):
 
     def __init__(
         self,
-        mobject: "Mobject",
+        mobject: Mobject,
         scale_factor: float = 1.2,
         color: str = YELLOW,
         rate_func: Callable[[float, Optional[float]], np.ndarray] = there_and_back,
@@ -158,7 +158,7 @@ def __init__(
         self.scale_factor = scale_factor
         super().__init__(mobject, rate_func=rate_func, **kwargs)
 
-    def create_target(self) -> "Mobject":
+    def create_target(self) -> Mobject:
         target = self.mobject.copy()
         target.scale(self.scale_factor)
         target.set_color(self.color)
@@ -348,7 +348,7 @@ def __init__(self, vmobject, n_segments=10, time_width=0.1, remover=True, **kwar
     message="Use Create then FadeOut to achieve this effect.",
 )
 class ShowCreationThenFadeOut(Succession):
-    def __init__(self, mobject: "Mobject", remover: bool = True, **kwargs) -> None:
+    def __init__(self, mobject: Mobject, remover: bool = True, **kwargs) -> None:
         super().__init__(Create(mobject), FadeOut(mobject), remover=remover, **kwargs)
 
 
@@ -397,7 +397,7 @@ def construct(self):
 
     def __init__(
         self,
-        mobject: "Mobject",
+        mobject: Mobject,
         direction: np.ndarray = UP,
         amplitude: float = 0.2,
         wave_func: Callable[[float], float] = smooth,
@@ -516,7 +516,7 @@ def construct(self):
 
     def __init__(
         self,
-        mobject: "Mobject",
+        mobject: Mobject,
         scale_value: float = 1.1,
         rotation_angle: float = 0.01 * TAU,
         n_wiggles: int = 6,
@@ -544,8 +544,8 @@ def get_rotate_about_point(self) -> np.ndarray:
 
     def interpolate_submobject(
         self,
-        submobject: "Mobject",
-        starting_submobject: "Mobject",
+        submobject: Mobject,
+        starting_submobject: Mobject,
         alpha: float,
     ) -> None:
         submobject.points[:, :] = starting_submobject.points