Create a simple "real world" regexp benchmark [LUCENE-9986]

For issues like #11022, where we are struggling to decide which low-level optimizations to make for our (complicated!) `determinize` method, it would really help to have a large, real-world corpus of regexps to evaluate performance metrics of our automata operations, like CPU and HEAP required to parse the regexp and determinize.

Does anyone know of such an existing, hopefully compatibly licensed, corpus?

Probably we would add these benchmarks to `luceneutil`.

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Migrated from [LUCENE-9986](https://issues.apache.org/jira/browse/LUCENE-9986) by Michael McCandless (@mikemccand)