IF NOT EXISTS doesn't work for EDGE [@out,@in] index (#2721)

Fixing issue on creating indexes on edges

(cherry picked from commit 96f4752)

Author: carlos-rodrigues-8x8

engine/src/main/java/com/arcadedb/query/sql/parser/CreateIndexStatement.java

@@ -111,6 +111,7 @@ else if (typeAsString.equalsIgnoreCase("UNIQUE")) {
 
     database.getSchema().buildTypeIndex(typeName.getStringValue(), fields)
         .withType(indexType)
+        .withIgnoreIfExists(ifNotExists)
         .withUnique(unique)
         .withPageSize(LSMTreeIndexAbstract.DEF_PAGE_SIZE)
         .withNullStrategy(nullStrategy)