add fuzz test for set env utility function

[shovanmaity]

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Checklist:

• [ ] Fixes #
• [ ] Labelled this PR & related issue with documentation tag
• [ ] PR messages has document related information
• [ ] Labelled this PR & related issue with breaking-changes tag
• [ ] PR messages has breaking changes related information
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• [ ] PR messages has upgrade related information
• [ ] Commit has unit tests
• [ ] Commit has integration tests