Blocked job when sending a force delete

When sending a DELETE command to a grpc-client job

```
[02:34:24.321] Processing job 'load' (1) in state Running
[02:34:24.537] Driver deleting job '1'
[02:34:25.323] Processing job 'load' (1) in state Deleting
[02:34:25.323] Deleting job 'load' (1)
[02:34:25.331] Stopping heartbeat (load:1)
[02:34:25.331] Heartbeat stopped for (load:1)
[02:34:25.332] Stopping counters event pipes for job 'load' (1)
[02:34:25.332] [WARNING] No event source open for job 'load' (1)
[02:34:25.583] Removing container 54a2a35de5de7f4cf6dd08e1d1a4b4225db4788f6a8d3500acaff82883b15b05
[02:34:25.604] Removing image benchmarks_go-grpc-client and its parents
[02:34:25.622] Process stopped (Stopped)
[02:34:25.625] Deleting directory '/tmp/benchmarks-agent/benchmarks-server-1/p01h4nam.2g1'
[02:34:25.651] Stopped -> Deleted (load:1)
[02:34:26.122] Driver stopping job '1'
[02:34:26.322] Processing job 'load' (1) in state Stopping
[02:34:26.323] Stopping job 'load' (1)
[02:34:27.322] Processing job 'load' (1) in state Stopping
[02:34:27.322] Stopping job 'load' (1)
[02:34:28.321] Processing job 'load' (1) in state Stopping
[02:34:28.321] Stopping job 'load' (1)
[02:34:29.320] Processing job 'load' (1) in state Stopping
[02:34:29.320] Stopping job 'load' (1)
[02:34:30.320] Processing job 'load' (1) in state Stopping
[02:34:30.320] Stopping job 'load' (1)
[02:34:31.325] Processing job 'load' (1) in state Stopping
[02:34:31.325] Stopping job 'load' (1)
[02:34:32.325] Processing job 'load' (1) in state Stopping
[02:34:32.325] Stopping job 'load' (1)
[02:34:33.327] Processing job 'load' (1) in state Stopping
[02:34:33.327] Stopping job 'load' (1)
[02:34:34.326] Processing job 'load' (1) in state Stopping
```