remove async_await feature gate

then we can build with beta as well

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

api-test/src/bin/api-test.rs

@@ -1,5 +1,3 @@
-#![feature(async_await)]
-
 use std::io;
 use std::path::Path;
 

proxmox-api-macro/tests/basic.rs

@@ -1,5 +1,3 @@
-#![feature(async_await)]
-
 use bytes::Bytes;
 use failure::{bail, Error};
 use serde_json::Value;

proxmox-api-macro/tests/verification.rs

@@ -1,5 +1,3 @@
-#![feature(async_await)]
-
 use bytes::Bytes;
 use failure::{bail, Error};
 use serde_json::{json, Value};

proxmox-api/tests/cli.rs

@@ -1,5 +1,3 @@
-#![feature(async_await)]
-
 use bytes::Bytes;
 
 use proxmox_api::cli;

proxmox-api/tests/router.rs

@@ -1,5 +1,3 @@
-#![feature(async_await)]
-
 use bytes::Bytes;
 use serde_json::Value;