Allow customizing order for AuditingEntityCallback and ValidatingEntityCallback

[yangchef1]

Hi @mp911de, as suggested in #4914, I've submitted a PR to address the issue.
Let me know if there's anything you'd like me to adjust or improve. Thanks!

Allow customizing order for AuditingEntityCallback and ValidatingEntityCallback. Added corresponding test cases for this functionality.

Closes #4914

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[yangchef1]

Hi @mp911de , Just wanted to kindly follow up on this PR. Please let me know if there's anything I can do to help move it forward. Thanks again for your time and feedback!

[mp911de]

Thank you for your contribution. That's merged and polished now.