unique_name should not be translated

Fixes #1993574 [Calibre 6.7.1* (source): Virtual library madness](https://bugs.launchpad.net/calibre/+bug/1993574)

src/calibre/gui2/actions/manage_categories.py

@@ -25,12 +25,11 @@ class ManageCategoriesAction(InterfaceAction):
         self.hidden_menu = QMenu()
         self.shortcut_action = self.create_menu_action(
                         menu=self.hidden_menu,
-                        unique_name=_('Manage categories'),
+                        unique_name='Manage categories',
                         text=_('Manage categories: authors, tags, series, etc.'),
                         icon='tags.png',
                         triggered=self.show_menu)
 
-
     # We want to show the menu when a shortcut is used. Apparently the only way
     # to do that is to scan the toolbar(s) for the action button then exec the
     # associated menu. The search is done here to take adding and removing the

src/calibre/gui2/actions/saved_searches.py

@@ -71,7 +71,7 @@ class SavedSearchesAction(InterfaceAction):
         self.hidden_menu = QMenu()
         self.shortcut_action = self.create_menu_action(
                         menu=self.hidden_menu,
-                        unique_name=_('Saved searches'),
+                        unique_name='Saved searches',
                         text=_('Show a menu of saved searches'),
                         icon='folder_saved_search.png',
                         triggered=self.show_menu)

src/calibre/gui2/bars.py

@@ -17,6 +17,7 @@ from calibre.gui2.throbber import ThrobbingButton
 from polyglot.builtins import itervalues
 from calibre.gui2.widgets2 import RightClickButton
 
+
 class RevealBar(QWidget):  # {{{
 
     def __init__(self, parent):