### Apache Airflow version

main (development)

### Operating System

macOS 11.5.2

### Versions of Apache Airflow Providers

_No response_

### Deployment

Virtualenv installation

### Deployment details

_No response_

### What happened

If your first try fails and you have retries enabled, the subsequent tries skip right to the final `next_method(**next_kwargs)` instead of starting with `execute` again.

### What you expected to happen

Like we reset things like start date, we should wipe `next_method` and `next_kwargs` so we can retry the task from the beginning.

### How to reproduce

_No response_

### Anything else

_No response_

### Are you willing to submit PR?

- [X] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

tests/models/test_taskinstance.py
"""
        Test the availability of variables in templates
        """
        Variable.set('a_variable', {'a': {'test': 'value'}}, serialize_json=True)
        ti = create_task_instance()
        context = ti.get_template_context()
        result = ti.task.render_template(content, context)
        assert result == expected_output
    def test_template_with_json_variable_missing(self, create_task_instance):
        ti = create_task_instance()
        context = ti.get_template_context()
        with pytest.raises(KeyError):
            ti.task.render_template('{{ var.json.get("missing_variable") }}', context)
    def test_execute_callback(self, create_task_instance):