Use options in_session

[RHL120]

Checklist

• [ ] Closing issues: #issue
• [ ] Mark this if you consider it ready to merge
• [ ] I've added tests (optional)
• [ ] I wrote some documentation

Description

This PR remove the atoi function because it is unnecessary and makes the return type of getenv an Option<i32> because this is how it should be. The rest of the changes are due to nvim complaining about mixed indentation