Using plural Tabs for consistency with other menus

Source commit: f722dd3aabc2eba6ba71a3785a9efb5d98a0b705

source/forms/ScpCommander.dfm

@@ -410,7 +410,7 @@ inherited ScpCommanderForm: TScpCommanderForm
         end
       end
       object TBXSubmenuItem29: TTBXSubmenuItem
-        Caption = '&Tab'
+        Caption = '&Tabs'
         HelpKeyword = 'ui_commander_menu#tab'
         Hint = 'Tab commands'
         object TBXSubmenuItem30: TTBXSubmenuItem

source/forms/ScpExplorer.dfm

@@ -287,7 +287,7 @@ inherited ScpExplorerForm: TScpExplorerForm
         end
       end
       object TBXSubmenuItem29: TTBXSubmenuItem
-        Caption = '&Tab'
+        Caption = '&Tabs'
         HelpKeyword = 'ui_explorer_menu#tab'
         Hint = 'Tab commands'
         object TBXItem113: TTBXItem