Update Request.zep

[zikezhang]

enhance getScheme() function.

Hello!

• Type: bug fix | new feature | code quality | documentation
• Link to issue:

In raising this pull request, I confirm the following:

• [x] I have read and understood the Contributing Guidelines
• [x] I have checked that another pull request for this purpose does not exist
• [x] I wrote some tests for this PR
• [ ] I have updated the relevant CHANGELOG
• [ ] I have created a PR for the documentation about this change

Small description of change:

Thanks