DOC: Fix deprecations in GTK4 embedding examples

Author: QuLogic

galleries/examples/user_interfaces/embedding_in_gtk4_panzoom_sgskip.py

@@ -44,10 +44,9 @@ def on_activate(app):
     toolbar = NavigationToolbar(canvas)
     vbox.append(toolbar)
 
-    win.show()
+    win.present()
 
 
-app = Gtk.Application(
-    application_id='org.matplotlib.examples.EmbeddingInGTK4PanZoom')
+app = Gtk.Application(application_id='org.matplotlib.examples.EmbeddingInGTK4PanZoom')
 app.connect('activate', on_activate)
 app.run(None)

galleries/examples/user_interfaces/embedding_in_gtk4_sgskip.py

@@ -39,7 +39,7 @@ def on_activate(app):
     canvas.set_size_request(800, 600)
     sw.set_child(canvas)
 
-    win.show()
+    win.present()
 
 
 app = Gtk.Application(application_id='org.matplotlib.examples.EmbeddingInGTK4')