fix(postgres): format unicode error messages from driver

[thalesmg]

Fixes https://emqx.atlassian.net/browse/EMQX-11024

Sample error:

{error, error, <<"42501">>, insufficient_privilege,
<<229,175,185,232,161,168,32,109,113,116,116,95,117,115,101,114,32,230,157,131,233,153,144,228,184,141,229,164,159>>,
[]}

Simulating the error log:

2023-10-11T20:28:31.666871+00:00 [error] mfa: emqx_connector_pgsql:deleteme/0(570), driver_error_code: <<"42501">>, driver_error_codename: insufficient, driver_error_message: 对表 mqtt_user 权限不够, driver_raw_reason: {error,error,<<"42501">>,insufficient,<<229,175,185,232,161,168,32,109,113,116,116,95,117,115,101,114,32,230,157,131,233,153,144,228,184,141,229,164,159>>,[]}, driver_severity: error

Summary

🤖 Generated by Copilot at 58c40bb

Improved error logging and updated version for emqx_connector. The pull request enhances the log messages for various error events in the emqx_connector_pgsql module and updates the version number of the emqx_connector application to 0.1.33.

PR Checklist

Please convert it to a draft if any of the following conditions are not met. Reviewers may skip over until all the items are checked:

• Added tests for the changes
• Added property-based tests for code which performs user input validation
• Changed lines covered in coverage report
• Change log has been added to changes/(ce|ee)/(feat|perf|fix)-<PR-id>.en.md files
• For internal contributor: there is a jira ticket to track this change
• Created PR to emqx-docs if documentation update is required, or link to a follow-up jira ticket
• Schema changes are backward compatible

Checklist for CI (.github/workflows) changes

• If changed package build workflow, pass this action (manual trigger)
• Change log has been added to changes/ dir for user-facing artifacts update