Refactor fetch APIs in userstore.ts to SWR hooks

[DonOmalVindula]

Purpose

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Related Issues

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Checklist

• e2e cypress tests locally verified. (for internal contributers)
• Manual test round performed and verified.
• UX/UI review done on the final implementation.
• Documentation provided. (Add links if there are any)
• Relevant backend changes deployed and verified
• Unit tests provided. (Add links if there are any)
• Integration tests provided. (Add links if there are any)

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• Followed secure coding standards in http://wso2.com/technical-reports/wso2-secure-engineering-guidelines
• Ran FindSecurityBugs plugin and verified report
• Confirmed that this PR doesn't commit any keys, passwords, tokens, usernames, or other secrets

[wso2-jenkins-bot]

⚠️ No Changeset found

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