SQL hooks can't execute

[edgarrmondragon]

SQL hooks before_run_sql and after_run_sql fail to execute with the following error message:

Traceback (most recent call last):
  File "/project/.meltano/loaders/target-snowflake/venv/bin/target-snowflake", line 8, in <module>
    sys.exit(cli())
  File "/project/.meltano/loaders/target-snowflake/venv/lib/python3.8/site-packages/target_snowflake/__init__.py", line 57, in cli
    main(args.config)
  File "/project/.meltano/loaders/target-snowflake/venv/lib/python3.8/site-packages/target_snowflake/__init__.py", line 51, in main
    target_tools.main(target)
  File "/project/.meltano/loaders/target-snowflake/venv/lib/python3.8/site-packages/target_postgres/target_tools.py", line 28, in main
    stream_to_target(input_stream, target, config=config)
  File "/project/.meltano/loaders/target-snowflake/venv/lib/python3.8/site-packages/target_postgres/target_tools.py", line 44, in stream_to_target
    _run_sql_hook('before_run_sql', config, target)
  File "/project/.meltano/loaders/target-snowflake/venv/lib/python3.8/site-packages/target_postgres/target_tools.py", line 188, in _run_sql_hook
    with target.conn.cursor() as cur:
AttributeError: 'SnowflakeTarget' object has no attribute 'conn'

Seems to be caused by this target using a different attribute name for the SQLAlchemy connection (self.connection instead of self.conn).