Use less time on recaptures

Credit for the idea goes to peregrine on discord.

Passed STC 10+0.1:
https://tests.stockfishchess.org/tests/view/662652623fe04ce4cefc48cf
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 75712 W: 19793 L: 19423 D: 36496
Ptnml(0-2): 258, 8487, 20023, 8803, 285

Passed LTC 60+0.6:
https://tests.stockfishchess.org/tests/view/6627495e3fe04ce4cefc59b6
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 49788 W: 12743 L: 12404 D: 24641
Ptnml(0-2): 29, 5141, 14215, 5480, 29

The code was updated slightly and tested for non-regression against the
original code at STC:

LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 41952 W: 10912 L: 10698 D: 20342
Ptnml(0-2): 133, 4825, 10835, 5061, 122
https://tests.stockfishchess.org/tests/view/662d84f56115ff6764c7e438

closes https://github.com/official-stockfish/Stockfish/pull/5189

Bench: 1836777

src/engine.h

@@ -20,24 +20,26 @@
 #define ENGINE_H_INCLUDED
 
 #include <cstddef>
+#include <cstdint>
 #include <functional>
 #include <optional>
 #include <string>
 #include <string_view>
 #include <utility>
 #include <vector>
-#include <cstdint>
 
 #include "nnue/network.h"
 #include "position.h"
 #include "search.h"
+#include "syzygy/tbprobe.h"  // for Stockfish::Depth
 #include "thread.h"
 #include "tt.h"
 #include "ucioption.h"
-#include "syzygy/tbprobe.h"  // for Stockfish::Depth
 
 namespace Stockfish {
 
+enum Square : int;
+
 class Engine {
    public:
     using InfoShort = Search::InfoShort;
@@ -50,7 +52,7 @@ class Engine {
     std::uint64_t perft(const std::string& fen, Depth depth, bool isChess960);
 
     // non blocking call to start searching
-    void go(const Search::LimitsType&);
+    void go(Search::LimitsType&);
     // non blocking call to stop searching
     void stop();
 
@@ -92,6 +94,7 @@ class Engine {
 
     Position     pos;
     StateListPtr states;
+    Square       capSq;
 
     OptionsMap           options;
     ThreadPool           threads;
@@ -104,4 +107,4 @@ class Engine {
 }  // namespace Stockfish
 
 
-#endif  // #ifndef ENGINE_H_INCLUDED
+#endif  // #ifndef ENGINE_H_INCLUDED