fix(core): adjust log message placeholder

[martynassateika]

Use %s instead of $s for the log message placeholder when logging the response code received from Redshift.

Description

This adjusts the log placeholder to avoid TypeError being raised when constructing the log message.

Motivation and Context

This change allows us to inspect the response code returned from Redshift. I was seeing "Server refuses SSL" messages from the driver, and after increasing the log level to DEBUG thought I would see what the code actually was, but then saw this in the logs instead:

[2024-04-02 16:40:28,247] Sending SSLRequestMessage to BE
[2024-04-02 16:40:28,279] Failed to emit log record
[2024-04-02 16:40:28,280] Traceback (most recent call last):
[2024-04-02 16:40:28,280]   File "/usr/local/airflow/config/cloudwatch_logging.py", line 162, in emit
    self.handler.emit(record)
[2024-04-02 16:40:28,281]   File "/usr/local/airflow/.local/lib/python3.11/site-packages/watchtower/__init__.py", line 396, in emit
    if message.getMessage() == "":
       ^^^^^^^^^^^^^^^^^^^^
[2024-04-02 16:40:28,281]   File "/usr/local/lib/python3.11/logging/__init__.py", line 377, in getMessage
    msg = msg % self.args
          ~~~~^~~~~~~~~~~
[2024-04-02 16:40:28,281] TypeError: not all arguments converted during string formatting
[2024-04-02 16:40:28,281] Task failed with exception
Traceback (most recent call last):
  File "/usr/local/airflow/.local/lib/python3.11/site-packages/airflow/models/taskinstance.py", line 433, in _execute_task
    result = execute_callable(context=context, **execute_callable_kwargs)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/airflow/.local/lib/python3.11/site-packages/airflow/sensors/base.py", line 265, in execute
    raise e
  File "/usr/local/airflow/.local/lib/python3.11/site-packages/airflow/sensors/base.py", line 247, in execute
    poke_return = self.poke(context)
                  ^^^^^^^^^^^^^^^^^^
  File "/usr/local/airflow/.local/lib/python3.11/site-packages/airflow/providers/common/sql/sensors/sql.py", line 96, in poke
    records = hook.get_records(self.sql, self.parameters)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/airflow/.local/lib/python3.11/site-packages/airflow/providers/common/sql/hooks/sql.py", line 261, in get_records
    return self.run(sql=sql, parameters=parameters, handler=fetch_all_handler)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/airflow/.local/lib/python3.11/site-packages/airflow/providers/common/sql/hooks/sql.py", line 391, in run
    with closing(self.get_conn()) as conn:
                 ^^^^^^^^^^^^^^^
  File "/usr/local/airflow/.local/lib/python3.11/site-packages/airflow/providers/amazon/aws/hooks/redshift_sql.py", line 200, in get_conn
    return redshift_connector.connect(**conn_kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/airflow/.local/lib/python3.11/site-packages/redshift_connector/__init__.py", line 376, in connect
    return Connection(
           ^^^^^^^^^^^
  File "/usr/local/airflow/.local/lib/python3.11/site-packages/redshift_connector/core.py", line 657, in __init__
    raise InterfaceError("Server refuses SSL")
redshift_connector.error.InterfaceError: Server refuses SSL

This updates the log message placeholder, so it is consistent with other messages in core.py.

Testing

As the code resides in core.py which has quite a low test coverage, I instead set up the following file to verify my changes:

import logging

if __name__ == '__main__':
    _logger: logging.Logger = logging.getLogger(__name__)
    logging.basicConfig(level=logging.DEBUG)
    resp = bytes([1, 2, 3])
    _logger.debug("Server response code when attempting to establish ssl connection: %s", resp)
    _logger.debug("Server response code when attempting to establish ssl connection: $s", resp)

Output:

DEBUG:__main__:Server response code when attempting to establish ssl connection: b'\x01\x02\x03'
--- Logging error ---
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/logging/__init__.py", line 1110, in emit
    msg = self.format(record)
          ^^^^^^^^^^^^^^^^^^^
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/logging/__init__.py", line 953, in format
    return fmt.format(record)
           ^^^^^^^^^^^^^^^^^^
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/logging/__init__.py", line 687, in format
    record.message = record.getMessage()
                     ^^^^^^^^^^^^^^^^^^^
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/logging/__init__.py", line 377, in getMessage
    msg = msg % self.args
          ~~~~^~~~~~~~~~~
TypeError: not all arguments converted during string formatting
Call stack:
  File "/Users/martynas/IdeaProjects/amazon-redshift-python-driver/test/log_test.py", line 8, in <module>
    _logger.debug("Server response code when attempting to establish ssl connection: $s", resp)
Message: 'Server response code when attempting to establish ssl connection: $s'
Arguments: (b'\x01\x02\x03',)

Screenshots (if appropriate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Checklist

• Local run of ./build.sh succeeds
• Code changes have been run against the repository's pre-commit hooks
• Commit messages follow Conventional Commit Specification
• I have read the README document
• I have added tests to cover my changes
• I have run all unit tests using pytest test/unit and they are passing.

• By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.