Enable annotations to set null value to nullable properties.

[Chaoba]

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Fixes: < Link to related issues that will be fixed by this pull request, if they exist >

Pull request checklist:

• Briefly describe the changes in this PR.
• Include before/after visuals or gifs if this PR includes visual changes.
• Write tests for all new functionality. If tests were not written, please explain why.
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Summary of changes

In the past, we ignore null values while users set them to annotation nullable properties so that users are not able to remove previously set properties.
In this pr, the properties will be removed from annotation if users set null value.

User impact (optional)