[BUG] Errors with snowflake-sqlalchemy 1.7.0

[TrangPham]

Describe the bug

https://pypi.org/project/snowflake-sqlalchemy/1.7.0/ Released on Nov 21st

will cause the project to error on:

ImportError while loading conftest '/Users/phamt/code/work/great_expectations/tests/conftest.py'.
tests/conftest.py:74: in <module>
    from great_expectations.self_check.util import (
great_expectations/self_check/util.py:337: in <module>
    "BOOLEAN": snowflake.snowflakedialect.BOOLEAN,
E   AttributeError: module 'snowflake.sqlalchemy.snowdialect' has no attribute 'BOOLEAN'

To Reproduce
Please include your great_expectations.yml config, the code you’re executing that causes the issue, and the full stack trace of any error(s).

Install GX with https://pypi.org/project/snowflake-sqlalchemy/1.7.0 and run any tests

Expected behavior
A clear and concise description of what you expected to happen.

No error should happen

Environment (please complete the following information):

• Operating System: MacOS
• Great Expectations Version: latest/dev env
• Data Source: Snowflake
• Cloud environment: N/A

Additional context
Add any other context about the problem here.

This was fixed yesterday: snowflakedb/snowflake-sqlalchemy#551

[TrangPham]

Suggestion: pin the current version to 1.6.1 until a new version is out/1.7 is yanked