MNT: Remove key_press and button_press from FigureManager

This removes these methods following the deprecation.

Author: greglucas

doc/api/next_api_changes/removals/23079-GL.rst

@@ -0,0 +1,5 @@
+``key_press`` and ``button_press`` have been removed from FigureManager
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Trigger the events directly on the canvas using
+``canvas.callbacks.process(event.name, event)`` for key and button events.

lib/matplotlib/backend_bases.py

@@ -2816,23 +2816,6 @@ def full_screen_toggle(self):
     def resize(self, w, h):
         """For GUI backends, resize the window (in physical pixels)."""
 
-    @_api.deprecated(
-        "3.4", alternative="self.canvas.callbacks.process(event.name, event)")
-    def key_press(self, event):
-        """
-        Implement the default Matplotlib key bindings defined at
-        :ref:`key-event-handling`.
-        """
-        if rcParams['toolbar'] != 'toolmanager':
-            key_press_handler(event)
-
-    @_api.deprecated(
-        "3.4", alternative="self.canvas.callbacks.process(event.name, event)")
-    def button_press(self, event):
-        """The default Matplotlib button actions for extra mouse buttons."""
-        if rcParams['toolbar'] != 'toolmanager':
-            button_press_handler(event)
-
     def get_window_title(self):
         """
         Return the title text of the window containing the figure, or None