disable razoring when try to find short win only when tthit

Passed f20 nonregressive LTC:
Book: f20-base-8k
TC: 60+0.6
Total/Win/Draw/Lose: 27280 / 13694 / 179 / 13407
PTNML: 2018 / 88 / 9283 / 91 / 2160
WinRate: 50.53%
ELO: 3.15[-1.26, 7.51]
LOS: 91.99
LLR: 3.18[-2.94, 2.94]

bench 6e18e82c
bench (msvc clang) 6fb684cd

Rapfi/search/ab/search.cpp

@@ -844,7 +844,9 @@ Value search(Board &board, SearchStack *ss, Value alpha, Value beta, Depth depth
     }
 
     // Step 7. Razoring with VCF (~55 elo)
-    if (!PvNode && eval + razorMargin<Rule>(depth) < alpha) {
+    if (!PvNode
+        && (alpha < VALUE_MATE_IN_MAX_PLY || !ttHit)  // We are not searching for a short win
+        && eval + razorMargin<Rule>(depth) < alpha) {
         return vcfsearch<Rule, NonPV>(board, ss, alpha, alpha + 1);
     }