⚖ Add basic knight outpost bonus only when the knight is centered and can't be attacked by minor pieces II - single increment

[eduherminio]

Iterating from:

• https://github.com/lynx-chess/Lynx/pull/614
• https://github.com/lynx-chess/Lynx/pull/616-

8+0.08

Score of Lynx-eval-knight-outposts-opponent-side-no-attackable-by-minor-piece-2440-win-x64 vs Lynx 2428 - main: 2766 - 2745 - 3399  [0.501] 8910
...      Lynx-eval-knight-outposts-opponent-side-no-attackable-by-minor-piece-2440-win-x64 playing White: 1862 - 872 - 1721  [0.611] 4455
...      Lynx-eval-knight-outposts-opponent-side-no-attackable-by-minor-piece-2440-win-x64 playing Black: 904 - 1873 - 1678  [0.391] 4455
...      White vs Black: 3735 - 1776 - 3399  [0.610] 8910
Elo difference: 0.8 +/- 5.7, LOS: 61.1 %, DrawRatio: 38.1 %
SPRT: llr -0.244 (-8.4%), lbound -2.25, ubound 2.89

40+0.4 [0, 3]

Score of Lynx-eval-knight-outposts-opponent-side-no-attackable-by-minor-piece-2440-win-x64 vs Lynx 2435 - main: 3422 - 3516 - 5399  [0.496] 12337
...      Lynx-eval-knight-outposts-opponent-side-no-attackable-by-minor-piece-2440-win-x64 playing White: 2557 - 955 - 2657  [0.630] 6169
...      Lynx-eval-knight-outposts-opponent-side-no-attackable-by-minor-piece-2440-win-x64 playing Black: 865 - 2561 - 2742  [0.363] 6168
...      White vs Black: 5118 - 1820 - 5399  [0.634] 12337
Elo difference: -2.6 +/- 4.6, LOS: 13.0 %, DrawRatio: 43.8 %
SPRT: llr -2.26 (-78.2%), lbound -2.25, ubound 2.89 - H0 was accepted