fix: unnecessary addition character appended on wallet.json

[kneerose]

List of changes

• Fix unnecessary addition characters that are appended to the wallet.json file while updating the file.

Checklist

• related issue
• My changes generate no new warnings
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the changelog
• I have added tests that prove my fix is effective or that my feature works

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[github-actions]

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[github-actions]

✅ All checks succeeded