Consolidate repetitions (#1062)

STC
Elo   | 0.01 +- 1.11 (95%)
SPRT  | 8.0+0.08s Threads=1 Hash=16MB
LLR   | 2.90 (-2.25, 2.89) [-2.75, 0.25]
Games | N: 92160 W: 23272 L: 23270 D: 45618
Penta | [273, 10110, 25311, 10114, 272]
https://recklesschess.space/test/15166/

No functional change.

Bench: 3634130

Author: protonspring

src/board/makemove.rs

@@ -7,6 +7,7 @@ impl Board {
         self.state_stack.push(self.state);
         self.state.keys.toggle_side();
         self.state.keys.toggle_castling(self.state.castling);
+        self.state.repetition = 0;
 
         if self.en_passant() != Square::None {
             self.state.keys.toggle_en_passant(self.en_passant());
@@ -17,7 +18,6 @@ impl Board {
     pub fn make_null_move(&mut self) {
         self.increment_stack();
         self.state.plies_from_null = 0;
-        self.state.repetition = 0;
         self.state.captured = None;
         self.update_threats();
     }
@@ -101,8 +101,6 @@ impl Board {
         self.update_threats();
         self.validate_en_passant();
 
-        self.state.repetition = 0;
-
         let end = self.state.plies_from_null.min(self.fiftymove_clock() as usize);
 
         if end >= 4 {