don't compute GVN for string constants of length more than 50, as this results in a infinite loop 😕

Author: erik-krogh

ql/ql/src/codeql/GlobalValueNumbering.qll

@@ -129,6 +129,7 @@ private predicate classPredicateCallValueNumber(
 
 private predicate literalValueNumber(Literal lit, string value, Type t) {
   lit.(String).getValue() = value and
+  value.length() <= 50 and
   t instanceof StringClass
   or
   lit.(Integer).getValue().toString() = value and