Sometimes make merge-queue dead-lock

[tetsuharuohzeki]

Like https://github.com/voyagegroup/eslint-config-fluct/pull/116#issuecomment-347731386, popuko sometimes causes a dead lock.

[nekoya]

Yeah, I sometimes meet such stuation like this.

I suspect that the event from Travis was missed with some reason, but the details is not clear to me yet.

In this case, Popuko doesn't have remained task on eslint-config-fluct queue.

{
  "version": 0,
  "auto_merge": {
    "queue": [],
    "current_active": null
  }
}

[nekoya]

We met the case #248.

2018/03/20 18:03:40 info: could not get the info for #248
2018/03/20 18:03:40 debug: context canceled
2018/03/20 18:03:40 info: We treat it as 'mergeable' to avoid miss detection because we could not fetch the pr info,

These messages are published at isMergeble function.