This test generates random boolean queries and ensures that setting a minimum
number of matching SHOULD clauses returns a subset of the hits with the same
scores.

It already tries to work around accuracy loss due to arithmetic operations by
allowing a delta of up to one ulp between these two queries. However, sometimes
the delta can be higher.

For instance consider the following query that triggered the most recent test
failure: `(data:5 data:5 data:5 data:6 +data:6 data:Z data:X -data:1)~2`.
Without a minimum number of matching SHOULD clauses, it gets rewritten to
`(data:5^3 +data:6^2 data:Z data:X -data:1)`. So the score contribution of
`data:5` is computed as `(double) score(data:5) + (double) score(data:5) +
(double) score(data:5)` in one case, and `(double) (score(data:5: * 3f)`
(multiply first, then cast to a double) in the other case. The use of
`ReqOptSumScorer` also contributes accuracy losses as per existing comment, for
instance `data:6` is part of both the required and the optional clauses in the
first case, while it's only a required clauses (with a 2x boost) in the other
case. So accuracy loss accrues differently.

I don't think we should try too hard to avoid these accuracy losses, so I'm
instead increasing the leniency of the test.