officejs: fix a wrong ID in a PathTemplateItem object

Fixes an logged error while indexing:

    2024-03-07 23:44:21.997 WARNING CMFActivity Message dropped (no object found at path ('', 'erp5_portal_ec7d28d9ada99a2cad998125d59fc158', 'image_module', 'gadget_officejs_appstore_app_text_editor_icon_text_editor_png'))
    Traceback (most recent call last):
      File "/srv/slapgrid/slappart22/t/eje/soft/de456d85f70e1b1a086396326977c83c/parts/erp5/product/CMFActivity/ActivityTool.py", line 262, in getObject
        obj = self._getObject(activity_tool)
      File "/srv/slapgrid/slappart22/t/eje/soft/de456d85f70e1b1a086396326977c83c/parts/erp5/product/CMFActivity/ActivityTool.py", line 256, in _getObject
        obj = obj[id]
      File "/srv/slapgrid/slappart22/t/eje/soft/de456d85f70e1b1a086396326977c83c/eggs/Zope-4.8.9+slapospatched002-py2.7.egg/OFS/ObjectManager.py", line 843, in __getitem__
        raise KeyError(key)
    KeyError: 'gadget_officejs_appstore_app_text_editor_icon_text_editor_png'