Adding Tooltip in Admin via only JS and CSS

[Rajinsharwar]

Adding Tooltip in Admin via only JS and CSS.

Trac ticket: https://core.trac.wordpress.org/ticket/51006

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This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[github-actions]

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[mukeshpanchal27]

Thanks for the PR. Left some initial feedbacks.

[Rajinsharwar]

Updated the PR based on the feedback @mukeshpanchal27 :)