testHiddenLuks (check_storage_hidden.TestStorage) is flaky

[cockpituous]

91% on verify/rhel-7-5-distropkg

• pull-10291

82% on verify/centos-7

• pull-10291

76% on verify/rhel-x

• pull-10572
• pull-10291
• pull-10248

94% on verify/fedora-28

• pull-10291

93% on verify/fedora-i386

• pull-10488
• pull-10291

78% on verify/fedora-29

• pull-10452
• pull-10301
• pull-10291

89% on verify/rhel-7-6-distropkg

• pull-10582
• pull-10569
• pull-10528
• pull-10291

Source material

{
  "test": [
    [
      "testHiddenLuks (check_storage_hidden.TestStorage)",
      24
    ]
  ],
  "status": [
    [
      "failure",
      24
    ]
  ],
  "tracker": [
    [
      null,
      24
    ]
  ],
  "context": [
    [
      "verify/rhel-7-5-distropkg",
      24
    ]
  ],
  "merged": [
    [
      true,
      22
    ],
    [
      false,
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    ]
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  "date": [
    "2018-07-30T21:13:00Z",
    "2018-10-14T10:53:43Z"
  ]
}
{
  "test": [
    [
      "testHiddenLuks (check_storage_hidden.TestStorage)",
      23
    ]
  ],
  "status": [
    [
      "failure",
      23
    ]
  ],
  "tracker": [
    [
      null,
      23
    ]
  ],
  "context": [
    [
      "verify/centos-7",
      23
    ]
  ],
  "merged": [
    [
      true,
      19
    ],
    [
      false,
      4
    ]
  ],
  "date": [
    "2018-08-07T09:50:42Z",
    "2018-10-14T10:51:03Z"
  ]
}
{
  "test": [
    [
      "testHiddenLuks (check_storage_hidden.TestStorage)",
      30
    ]
  ],
  "status": [
    [
      "failure",
      30
    ]
  ],
  "tracker": [
    [
      null,
      30
    ]
  ],
  "context": [
    [
      "verify/rhel-x",
      30
    ]
  ],
  "merged": [
    [
      true,
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    ],
    [
      false,
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    ]
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  "date": [
    "2018-07-24T08:41:19Z",
    "2018-11-13T19:52:28Z"
  ]
}
{
  "test": [
    [
      "testHiddenLuks (check_storage_hidden.TestStorage)",
      17
    ]
  ],
  "status": [
    [
      "failure",
      17
    ]
  ],
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    [
      null,
      17
    ]
  ],
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    [
      "verify/fedora-28",
      17
    ]
  ],
  "merged": [
    [
      true,
      16
    ],
    [
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    ]
  ],
  "date": [
    "2018-08-31T13:20:28Z",
    "2018-10-14T10:57:32Z"
  ]
}
{
  "test": [
    [
      "testHiddenLuks (check_storage_hidden.TestStorage)",
      15
    ]
  ],
  "status": [
    [
      "failure",
      15
    ]
  ],
  "tracker": [
    [
      null,
      15
    ]
  ],
  "context": [
    [
      "verify/fedora-i386",
      15
    ]
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    [
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  ],
  "date": [
    "2018-08-31T13:35:35Z",
    "2018-11-01T17:16:25Z"
  ]
}
{
  "test": [
    [
      "testHiddenLuks (check_storage_hidden.TestStorage)",
      14
    ]
  ],
  "status": [
    [
      "failure",
      14
    ]
  ],
  "tracker": [
    [
      null,
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    ]
  ],
  "context": [
    [
      "verify/fedora-29",
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  ],
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    [
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  ],
  "date": [
    "2018-09-04T17:55:58Z",
    "2018-10-27T07:57:37Z"
  ]
}
{
  "test": [
    [
      "testHiddenLuks (check_storage_hidden.TestStorage)",
      19
    ]
  ],
  "status": [
    [
      "failure",
      19
    ]
  ],
  "tracker": [
    [
      null,
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    ]
  ],
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    [
      "verify/rhel-7-6-distropkg",
      19
    ]
  ],
  "merged": [
    [
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      17
    ],
    [
      false,
      2
    ]
  ],
  "date": [
    "2018-09-21T14:16:24Z",
    "2018-11-15T15:02:34Z"
  ]
}