Remove duplicate and redundant code in Flet package

Eliminated a duplicate line in the ShareFile documentation, removed a repeated entry for 'BrowserConfiguration' in __all__, and simplified the ServiceRegistry default_factory in Page control. These changes improve code clarity and maintainability.

Author: FeodorFitsner

sdk/python/packages/flet/docs/types/sharefile.md

@@ -1,2 +1 @@
 {{ class_all_options("flet.ShareFile", separate_signature=False) }}
-{{ class_all_options("flet.ShareFile", separate_signature=False) }}

sdk/python/packages/flet/src/flet/__init__.py

@@ -643,7 +643,6 @@
     "BoxShape",
     "Brightness",
     "BrowserConfiguration",
-    "BrowserConfiguration",
     "BrowserContextMenu",
     "Button",
     "ButtonStyle",

sdk/python/packages/flet/src/flet/controls/page.py

@@ -385,7 +385,7 @@ class Page(BasePage):
     """
     TBD
     """
-    _services: ServiceRegistry = field(default_factory=lambda: ServiceRegistry())
+    _services: ServiceRegistry = field(default_factory=ServiceRegistry)
 
     def __post_init__(
         self,
@@ -395,8 +395,6 @@ def __post_init__(
         BasePage.__post_init__(self, ref)
         self._i = 1
         self.__session = weakref.ref(sess)
-
-        # page services
         self.__last_route = None
         self.__query: QueryString = QueryString(self)
         self.__authorization: Optional[Authorization] = None