Add SnowflakeCheckOperator, SnowflakeValueCheckOperator, and SnowflakeIntervalCheckOperator to Snowflake provider.

**Use case / motivation**

The SQL operator, as well as other provider DB operators, already support this functionality. It can prove useful for data quality use cases with Snowflake. It should be relatively easy to implement in the same fashion as [BigQuery's versions](https://github.com/apache/airflow/blob/main/airflow/providers/google/cloud/operators/bigquery.py#L101).

**Are you willing to submit a PR?**

Yep!

**Related Issues**

Not that I could find.
tests/providers/snowflake/operators/test_snowflake.py
def setUp(self):
        super().setUp()
        args = {'owner': 'airflow', 'start_date': DEFAULT_DATE}
        dag = DAG(TEST_DAG_ID, default_args=args)
        self.dag = dag
    @mock.patch(LONG_MOCK_PATH)
    def test_snowflake_operator(self, mock_get_hook):
        sql = """
        CREATE TABLE IF NOT EXISTS test_airflow (
            dummy VARCHAR(50)
        );
        """
        operator = SnowflakeOperator(task_id='basic_snowflake', sql=sql, dag=self.dag, do_xcom_push=False)
        
        operator.run(start_date=DEFAULT_DATE, end_date=DEFAULT_DATE, ignore_ti_state=True)