Add some missing Styles imports for type hinting

src/textual/widgets/_tree_control.py

@@ -9,6 +9,7 @@ from rich.text import Text, TextType
 from rich.tree import Tree
 from rich.padding import PaddingDimensions
 
+from textual.css.styles import Styles
 from .. import log
 from .. import events
 from ..reactive import Reactive

src/textual/widgets/tabs.py

@@ -12,6 +12,7 @@ from rich.text import Text
 
 from textual import events
 from textual._layout_resolve import layout_resolve, Edge
+from textual.css.styles import Styles
 from textual.keys import Keys
 from textual.reactive import Reactive
 from textual.renderables.opacity import Opacity