Add benchmarks for CombinedFieldsQuery

[jpountz]

It's so common to query multiple fields at once with the same query, we should have a benchmark for this case with the query that computes scores in a way that makes sense: CombinedFieldsQuery.

And hopefully we'll see a nice bump when LUCENE-10061 is implemented. :)

[jtibshirani]

Can this be closed now that https://github.com/mikemccand/luceneutil/pull/148 is merged?

[mikemccand]

I think almost! The hard part was already done in #148 (thank you @zacharymorn and @jpountz!). Maybe we could just add a few of these tasks into wikinightly.tasks, and tweak nightlyBench.py to add links to these new tasks when it writes the nightly index.html? Then we start tracking perf of this awesome query in nightlies ...

[zacharymorn]

I think almost! The hard part was already done in #148 (thank you @zacharymorn and @jpountz!). Maybe we could just add a few of these tasks into wikinightly.tasks, and tweak nightlyBench.py to add links to these new tasks when it writes the nightly index.html? Then we start tracking perf of this awesome query in nightlies ...

Oops didn't realize there's a github issue for this as well. I think adding it into nightly benchmark is a great suggestion! Let me take a look how it was done before, and will come up with something.