Change conf property from str to dict in SparkSqlOperator

[duhizjame]

Changes the conf property from str to dict in SparkSqlOperator
closes: #40507

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[potiuk]

Tests failing

[eladkal]

Can you resolve conflicts and rebase?

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 5 days if no further activity occurs. Thank you for your contributions.