Jenkins builds failing frequently with `AAA_PreCloudLock` error at runtime (test cloud setup)

Description

truncated exception:
```
[2019-10-01T22:19:05.576Z] 1) hex.AAA_PreCloudLock
[2019-10-01T22:19:05.576Z] java.lang.RuntimeException: Cloud size 1 under 4
[2019-10-01T22:19:05.576Z] at water.H2O.waitForCloudSize(H2O.java:1819)
[2019-10-01T22:19:05.576Z] at water.TestUtil.stall_till_cloudsize(TestUtil.java:94)
[2019-10-01T22:19:05.576Z] at water.TestUtil.stall_till_cloudsize(TestUtil.java:78)
[2019-10-01T22:19:05.576Z] at hex.AAA_PreCloudLock.setup(AAA_PreCloudLock.java:28)
```

Environment

None

Status

Assignee

New H2O Bugs

Fix versions

None

Reporter

Sebastien Poirier

Support ticket URL

None

Labels

Release Priority

None

Affected Spark version

None

Customer Request Type

None

Task progress

None

CustomerVisible

No

Components

Priority

Major
Configure