text: Title: TypeError raised from hidden_tag() on Jinja 3.0.0rc1
  Body: # Requirements
  ```
  click==8.0.0rc1
  Flask==2.0.0rc1
  Flask-WTF==0.14.3
  itsdangerous==2.0.0rc2
  Jinja2==3.0.0rc1
  MarkupSafe==2.0.0rc2
  Werkzeug==2.0.0rc4
  WTForms==2.3.3
  ```
  
  # Example
  ```
  import os
  from flask import Flask, render_template_string
  from flask_wtf import FlaskForm
  from wtforms import StringField
  from wtforms.validators import DataRequired
  from flask_wtf.csrf import CSRFProtect
  
  
  class MyForm(FlaskForm):
      name = StringField('name', validators=[DataRequired()])
  
  
  app = Flask(__name__)
  app.config['SECRET_KEY'] = os.urandom(24).hex()
  csrf = CSRFProtect(app)
  
  
  @app.route('/')
  def hello_world():
      form = MyForm()
      return render_template_string('''
      <form method="POST" action="/">
          {{ form.hidden_tag() }}
          {{ form.name.label }} {{ form.name(size=20) }}
          <input type="submit" value="Go">
      </form>
      ''', form=form)
  
  
  if __name__ == '__main__':
      app.run()
  
  ```
  
  # Traceback
  ```
  Traceback (most recent call last):
    File "/.../pre-venv/lib/python3.9/site-packages/flask/app.py", line 1971, in __call__
      return self.wsgi_app(environ, start_response)
    File "/.../pre-venv/lib/python3.9/site-packages/flask/app.py", line 1956, in wsgi_app
      response = self.handle_exception(e)
    File "/.../pre-venv/lib/python3.9/site-packages/flask/app.py", line 1953, in wsgi_app
      response = self.full_dispatch_request()
    File "/.../pre-venv/lib/python3.9/site-packages/flask/app.py", line 1454, in full_dispatch_request
      rv = self.handle_user_exception(e)
    File "/.../pre-venv/lib/python3.9/site-packages/flask/app.py", line 1452, in full_dispatch_request
      rv = self.dispatch_request()
    File "/.../pre-venv/lib/python3.9/site-packages/flask/app.py", line 1438, in dispatch_request
      return self.view_functions[rule.endpoint](**req.view_args)
    File "/.../app.py", line 21, in hello_world
      return render_template_string('''
    File "/.../pre-venv/lib/python3.9/site-packages/flask/templating.py", line 145, in render_template_string
      return _render(ctx.app.jinja_env.from_string(source), context, ctx.app)
    File "/.../pre-venv/lib/python3.9/site-packages/flask/templating.py", line 110, in _render
      rv = template.render(context)
    File "/.../pre-venv/lib/python3.9/site-packages/jinja2/environment.py", line 1127, in render
      self.environment.handle_exception()
    File "/.../pre-venv/lib/python3.9/site-packages/jinja2/environment.py", line 814, in handle_exception
      raise rewrite_traceback_stack(source=source)
    File "<template>", line 3, in top-level template code
      
    File "/.../pre-venv/lib/python3.9/site-packages/flask_wtf/form.py", line 133, in hidden_tag
      return Markup(
    File "/.../pre-venv/lib/python3.9/site-packages/jinja2/utils.py", line 843, in __init__
      super().__init__(*args, **kwargs)
  TypeError: object.__init__() takes exactly one argument (the instance to initialize)
  ```
  
  # Notes
  Using  `form.csrf_token` in the place of `hidden_tag()` in the template raises no exception.
  
  Also my assumption is that `hidden_tag()` does not require the existence of additional hidden form elements as I believe this works as expected on Flask 1.1.2.
  
  Thank you for the consideration in preparation for Flask 2.0