Add a test to make sure that negative effective values are filtered
Summary:
This is a partial backport of Core PR10637 : https://github.com/bitcoin/bitcoin/pull/10637/commits/73b5bf2cb40720bb4e4436ea63b5badf3d89ceb9
Depends on D3301
Test Plan:
make check
Reviewers: #bitcoin_abc, Fabien
Reviewed By: #bitcoin_abc, Fabien
Differential Revision: https://reviews.bitcoinabc.org/D3304