Added changed fields methods.

[TMRGZ]

• [x] You have read the Spring Data contribution guidelines.
• [x] You use the code formatters provided here and have them applied to your changes. Don’t submit any formatting related changes.
• [x] You submit test cases (unit or integration tests) that back your changes.
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[mp911de]

We do not want to broaden the interface in a way of introducing additional overloads. We might consider adding query derivation for revisions, however, that is something to be explored.