[FIX] web: prevent kwargs position confusion

The fith arguemnt of the search method in count in new API.
Passing all arguments as positional arguments will make the context passed for
the value of the `count` argument.

bbc67ec is a similar fix in 9.0

Closes #12830

addons/web/controllers/main.py

@@ -1432,7 +1432,7 @@ class ExportFormat(object):
 
         Model = request.session.model(model)
         context = dict(request.context or {}, **params.get('context', {}))
-        ids = ids or Model.search(domain, 0, False, False, context)
+        ids = ids or Model.search(domain, offset=0, limit=False, order=False, context=context)
 
         if not request.env[model]._is_an_ordinary_table():
             fields = [field for field in fields if field['name'] != 'id']