fix: add .env_sample file

[bL34cHig0]

Fixes Issue

My PR closes #578

👨‍💻 Changes proposed(What did you do ?)

I added the .env_sample file to the root of the project so users can configure the .env file stipulated in the installation section of README.md.

✔️ Check List (Check all the applicable boxes)

• [] My code follows the code style of this project.
• [] This PR does not contain plagiarized content.
• [] The title and description of the PR is clear and explains the approach.

Note to reviewers

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[Dun-sin]

You did great, thanks for contributing, I hope you will stick around and continue to contribute to this project.