[Bug]: shim occasionally fails to detect AWS EBS Volumes due to race condition #4001

Steps to reproduce

• start a dev environment in AWS with a volume attachment
• it may fail right away, if not, detach without terminating and reapply the run
• do this several times until failure

Actual behaviour

Runs fail with "prepareVolumes error: format and mount volume: get real device name: volume not found among block devices"

Expected behaviour

runs are successful without failure

dstack version

0.20.26

Server logs

Additional information

Caused by a race condition. shim is trying to get real device name before volume is ready