Fixes#11380, #11339
In prior versions of Gramps you could use the undo/redo keys to edit items in the text entries. This no longer works.
This is related to the changes to suppress odd characters and leading/trailing spaces. The Gtk.Entry.set_text() call is effectively clearing the undo/redo list at every keystroke or when you leave the field.
In this PR I move the odd characters cleanup into UndoableEntry.do_insert_text instead of MonitoredEntry.
I scanned the users of MonitoredEntry and they all appeared to use Glade files, I scanned the glade files for anyone using just plain Entry (none found), they all appeared to use UndoableEntry or ValidatableMaskedEntry, so this should cover everyone.