Further tweak statscore for captures
Even lower offset.
Passed STC:
https://tests.stockfishchess.org/tests/view/673a66d786d5ee47d953f070
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 63776 W: 16570 L: 16216 D: 30990
Ptnml(0-2): 178, 7371, 16478, 7641, 220
Passed LTC:
https://tests.stockfishchess.org/tests/view/673b2e2a86d5ee47d953f14b
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 156960 W: 39999 L: 39435 D: 77526
Ptnml(0-2): 96, 16965, 43803, 17511, 105
closes https://github.com/official-stockfish/Stockfish/pull/5686
Bench: 867931