squish test: investigate timeouts

squish tests jenkins job is timing out occasionally, a correct looking log would be:
```
16:56:44 SETTING DEFAULT CONFIG
16:56:44 FINISHED SETTING DEFAULT CONFIG
16:56:44 Data dir moved to datadel
16:56:44 Deleted the moved data dir
16:56:44 Toggled autorestart for the BLOCKSVR
16:59:06 Toggled autorestart for the BLOCKSVR
16:59:06 Stopped or restarted the BLOCKSVR
16:59:06 Toggled autorestart for the ISISDAE_01
16:59:06 Stopped or restarted the ISISDAE_01
```
whereas a timeout log looks like
```
16:59:06 SETTING DEFAULT CONFIG
16:59:06 FINISHED SETTING DEFAULT CONFIG
16:59:06 Data dir moved to datadel
16:59:06 Deleted the moved data dir
16:59:06 Toggled autorestart for the BLOCKSVR
23:42:41 Toggled autorestart for the BLOCKSVR
23:42:41 Stopped or restarted the BLOCKSVR
23:42:41 Toggled autorestart for the ISISDAE_01
23:42:41 Stopped or restarted the ISISDAE_01
```
The difference is a 6 hours 45 minutes break between the two `Toggled autorestart for the BLOCKSVR` lines. This delay length is the same in all the logs I have seen so far.

## acceptance criteria

source of delay identified and fixed