Remove the implementation of notify from Screen (#2996)

* Remove the implementation of notify on Screen

Screen inherits the one from Widget anyway. I always forget that Screen is a
Widget. O_o

* Remove imports that aren't needed any more

src/textual/screen.py

@@ -36,7 +36,6 @@
 from .css.query import NoMatches, QueryType
 from .dom import DOMNode
 from .geometry import Offset, Region, Size
-from .notifications import Notification, SeverityLevel
 from .reactive import Reactive
 from .renderables.background_screen import BackgroundScreen
 from .renderables.blank import Blank
@@ -940,30 +939,6 @@ def action_dismiss(
         """
         self.dismiss(result)
 
-    def notify(
-        self,
-        message: str,
-        *,
-        title: str = "",
-        severity: SeverityLevel = "information",
-        timeout: float = Notification.timeout,
-    ) -> Notification:
-        """Create a notification.
-
-        Args:
-            message: The message for the notification.
-            title: The title for the notification.
-            severity: The severity of the notification.
-            timeout: The timeout for the notification.
-
-        Returns:
-            The new notification.
-
-        See [`App.notify`][textual.app.App.notify] for the full
-        documentation for this method.
-        """
-        return self.app.notify(message, title=title, severity=severity, timeout=timeout)
-
 
 @rich.repr.auto
 class ModalScreen(Screen[ScreenResultType]):