fix(connector): don't log config/props that may contain sensitive information

[zwang28]

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What's changed and what's your intention?

This PR is a quick fix. I went through all tracing:: in connector crate, to find any potential ones.

1. rdkafka::ClientConfig::conf_map is not strong-typed. This PR simply removes it from log. We may leverage secure-string in the rdkafka lib in the future.
2. For ConnectorProperties and SinkParam, this PR again simply removes them from log. After SECRETS hopefully there's no more sensitive info in them. The reasons why I don't leverage secure-string now are
   • changes like feat(parser): redact SqlOption #14760 requires verbose serde implementation
   • SinkParam::properties is not strong-typed.

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