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
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import unittest
from unittest import mock
from airflow.models.dag import DAG
from airflow.providers.snowflake.operators.snowflake import SnowflakeOperator
from airflow.utils import timezone
DEFAULT_DATE = timezone.datetime(2015, 1, 1)
DEFAULT_DATE_ISO = DEFAULT_DATE.isoformat()
DEFAULT_DATE_DS = DEFAULT_DATE_ISO[:10]
TEST_DAG_ID = 'unit_test_dag'
LONG_MOCK_PATH = "airflow.providers.snowflake.operators.snowflake."
LONG_MOCK_PATH += 'SnowflakeOperator.get_hook'
class TestSnowflakeOperator(unittest.TestCase):