Tokio runtime creation failed

[Centaurus99]

Sometimes rattan panic here:

rattan/rattan-cli/src/main.rs

Lines 206 to 210 in 20e592c

	let runtime = tokio::runtime::Builder::new_current_thread()
	.enable_io()
	.enable_time()
	.build()
	.unwrap();

error.log

Now we sleep 0.1 secs before building runtime to temporarily mitigate this bug.