Fix signature of some more _close() methods [circle deploy] (mne-tools#13087)

Author: wmvanvliet

mne/viz/_figure.py

@@ -424,7 +424,7 @@ def _redraw(self, update_data=True, annotations=False):
         if annotations and not self.mne.is_epochs:
             self._draw_annotations()
 
-    def _close(self, event):
+    def _close(self, event=None):
         """Handle close events (via keypress or window [x])."""
         from matplotlib.pyplot import close