Add get methods to replace fetch_mob method. (#19)

* Add get methods to replace fetch_mob method.

* Update src/manim_data_structures/m_array.py

---------

Co-authored-by: Nikhil Iyer <[email protected]>

Author: DiegoCarra

Diff for: src/manim_data_structures/m_array.py

@@ -371,6 +371,18 @@ def fetch_mob(self, mob_target: MArrayElementComp) -> Mobject:
             return self.fetch_mob_label()
         else:
             return self
+        
+    def get_body(self) -> Square:
+        return self.fetch_mob_square()
+    
+    def get_value(self) -> Text:
+        return self.fetch_mob_value()
+    
+    def get_index(self) -> Text:
+        return self.fetch_mob_index()
+    
+    def get_label(self) -> Text:
+        return self.fetch_mob_label()
 
     def update_mob_value(
         self,