Schema for path-arguments duplicates input

Using a schema to validate/process the path arguments seems to pass the argument twice.
The data-dict of the marshmallow schema is passed as an argument and the value is passed as keyword-argument (probably by vanilla flask).

Note: This can be prevented by passing `as_kwargs = True` to the decorator

Code-Example:
```python
from flask.views import MethodView
from marshmallow import Schema
from marshmallow.fields import String
from flask_smorest import Blueprint

bp = Blueprint("pets", "pets", description="pet related operations", url_prefix="/api/pets")

class PetIdSchema(Schema):
pet_id = String(required=True)

@bp.route("/")
class SinglePet(MethodView):
"""route for operations on a single pet"""

@bp.arguments(PetIdSchema(), location="path")
def get(self, *args, **kwargs):
"""get information on this pet"""
print(f"args: {args} | kwargs: {kwargs}")
# prints: args: ({'pet_id': '600aed28e65f74c3a97f6f58'},) | kwargs: {'pet_id': '600aed28e65f74c3a97f6f58'}
pet_id = args[0]
return Pet.get_by_id(pet_id)
```

Start with the bp.arguments decorator and its handling of location="path" on Flask MethodView methods. Reproduce the example and compare the positional schema data with the keyword path argument, noting the as_kwargs=True behavior. Done means the path value is not unexpectedly supplied twice while existing decorator usage remains compatible.

Written by the indexing model from the issue text.