Support for Request v0.13 for retry-middleware

[coder3101]

Bug description

When trying to use reqwest v0.13.x with retry-middleware, the compiler reports error since retry-middleware depends on 0.12.x

To Reproduce

Use reqwest 0.13.x and retry-middleware in the same project

Expected behavior

Ideally a new release using the new reqwest 0.13.x should be made

Environment

• OS: Any
• Rust version: 1.91

Additional context