Use env variables in Github Actions docs (#5411)
## Summary
Use [Github
Actions](https://docs.github.com/en/actions/learn-github-actions/variables#defining-environment-variables-for-a-single-workflow)
`env` to define environment variables.
After:
<img width="751" alt="Screenshot 2024-07-24 at 17 24 23"
src="https://github.com/user-attachments/assets/9c7861f0-e95d-4778-96c0-261df539a0bd">
