Tweak continuation history bonus dependent on ply.
This patch is based on following tuning https://tests.stockfishchess.org/tests/view/6648b2eb308cceea45533abe by only using the tuned factors for the continuation history.
Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 99904 W: 25865 L: 25457 D: 48582
Ptnml(0-2): 281, 11705, 25578, 12101, 287
https://tests.stockfishchess.org/tests/view/6648c136308cceea45533af8
Passed LTC:
LLR: 2.96 (-2.94,2.94) <0.50,2.50>
Total: 36402 W: 9362 L: 9039 D: 18001
Ptnml(0-2): 20, 3952, 9951, 4241, 37
https://tests.stockfishchess.org/tests/view/6648ee3cb8fa20e74c39f3fd
closes https://github.com/official-stockfish/Stockfish/pull/5267
Bench: 1917762