Remove unsound quantifier reduction rules

Some of the quantifier reduction rules in oniguruma are invalid, leading to new
regular expressions with different semantics. This commit removes two such
reduction rules.

https://bugs.ruby-lang.org/issues/17341
ruby/ruby#3808

src/org/joni/ast/QuantifierNode.java

@@ -137,7 +137,6 @@ static enum ReduceType {
         AQ,         /* to '*?'   */
         QQ,         /* to '??'   */
         P_QQ,       /* to '+)??' */
-        PQ_Q,       /* to '+?)?' */
     }
 
     static final ReduceType[][]REDUCE_TABLE = {
@@ -146,7 +145,7 @@ static enum ReduceType {
       {A,       A,      DEL,    ASIS,   P_QQ,   DEL},  /* '+'  */
       {DEL,     AQ,     AQ,     DEL,    AQ,     AQ},   /* '??' */
       {DEL,     DEL,    DEL,    DEL,    DEL,    DEL},  /* '*?' */
-      {ASIS,    PQ_Q,   DEL,    AQ,     AQ,     DEL}   /* '+?' */
+      {ASIS,    ASIS,   ASIS,   AQ,     AQ,     DEL}   /* '+?' */
     };
 
 
@@ -193,16 +192,6 @@ public void reduceNestedQuantifier(QuantifierNode other) {
             other.greedy = true;
             return;
 
-        case PQ_Q:
-            setTarget(other);
-            lower = 0;
-            upper = 1;
-            greedy = true;
-            other.lower = 1;
-            other.upper = REPEAT_INFINITE;
-            other.greedy = false;
-            return;
-
         case ASIS:
             setTarget(other);
             return;