test(utils): add tests for theme mode toggle

[Neeraj-gagat]

Description

This pr adds interactions test for ThemeModeToggle enssuring correct theme changes

- Fixes: #299

these new tests increased coverage from 70% to 100%

image

[github-actions]

Thank you for opening this PR!

Before a maintainer takes a look, it would be really helpful if you could walk through your changes using GitHub's review tools.

Please take a moment to:

• Check the "Files changed" tab
• Leave comments on any lines for functions, comments, etc. that are important, non-obvious, or may need attention
• Clarify decisions you made or areas you might be unsure about and/or any future updates being considered.
• Finally, submit all the comments!

More information on how to conduct a self review:
https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/reviewing-proposed-changes-in-a-pull-request

This helps make the review process smoother and gives us a clearer understanding of your thought process.

Once you've added your self-review, we'll continue from our side. Thank you!

[Neeraj-gagat]

done with self reiew added tests in existing file theme-mode-toggle.test.tsx added test for interaction like clicking on light, dark, system and ensured it render icons for sun && moon