Sweep: Update readme to start with a friendly message that raises awarness about climate change

[Infrared1029]

Description

This pull request updates the README.md file to include a prominent message about Climate Change Awareness Month, encouraging visitors to take small actions that can lead to significant environmental benefits.

Summary

• Added a new section at the top of the README.md file.
• This section includes a centered paragraph with a bold message about Climate Change Awareness Month.
• A link to the United Nations climate change information page is provided to educate and encourage further action.

Fixes #1.

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[Infrared1029]

Rollback Files For Sweep

• [ ] Rollback changes to README.md

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