non async test runner

[sehz]

similar to #[fluvio_future::test] but support non async function.

#[cfg(test)]
mod test {
 
     // same as cargo test but initialize logging
     #[fluvio_future::test]
     fn test_add() {
           assert_eq!(1+1,2);
     }

    // uses async runtime
     #[fluvio_future::test]
     async fn test_add() {
           assert_eq!(1+2);
    }

}