Spring Enhance getTransactionAttribute for Clarity and Compatibility

This PR refines the getTransactionAttribute method to enhance clarity, reduce redundancy, and improve Java version compatibility.

Key changes include: - Using ternary operators for more concise null checks. - Consolidating cache null-check logic to eliminate code duplication. - Employing traditional instanceof checks for broader Java compatibility.

These optimizations aim to maintain the method's existing behavior while making the code more readable and easier to maintain, ensuring compatibility with a wider range of Java versions.

Tests confirm these changes do not affect the method's functionality. Feedback and further suggestions are welcome.

Comment From: snicoll

@junhkang thanks but we don't need to modify such hot code path that is completely internal. Some changes are also subjective and we prefer to apply those ourselves consistently.