Benchmark BnB in the worst case where it exhausts

Summary:
This is a partial backport of Core PR10637 : https://github.com/bitcoin/bitcoin/pull/10637/commits/76d2f068a4cbd2bfe50c166fe0babfc5f17acaf4

Depends on D3250

Test Plan:

make
./src/bench/bench_bitcoin

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D3303