Backport PR #23390 on branch 6.x (PR: Add missing __init__() calls in a couple of places) (#23393)

Author: meeseeksmachine

spyder/widgets/findreplace.py

@@ -72,6 +72,7 @@ class FindReplace(QWidget, SpyderShortcutsMixin):
 
     def __init__(self, parent, enable_replace=False):
         QWidget.__init__(self, parent)
+        SpyderShortcutsMixin.__init__(self)
         self.enable_replace = enable_replace
         self.editor = None
         self.is_code_editor = None

spyder/widgets/tabs.py

@@ -639,6 +639,7 @@ def __init__(self, parent, actions=None, menu=None,
                  split_index=0):
         BaseTabs.__init__(self, parent, actions, menu,
                           corner_widgets, menu_use_tooltips)
+        SpyderShortcutsMixin.__init__(self)
         tab_bar = TabBar(self, parent,
                          rename_tabs=rename_tabs,
                          split_char=split_char,