Fix replacement reference in RequestProtector app

bubble-server/src/main/java/bubble/app/request/RequestProtectorAppConfigDriver.java

@@ -72,7 +72,7 @@ public class RequestProtectorAppConfigDriver extends AppConfigDriverBase {
         if (replacementNode == null || replacementNode.textValue() == null) {
             throw invalidEx("err.requestProtector.headerReplacementRequired");
         }
-        final String replacement = regexNode.textValue().trim();
+        final String replacement = replacementNode.textValue().trim();
         if (empty(replacement)) throw invalidEx("err.requestProtector.headerReplacementRequired");
 
         final RequestProtectorConfig config = getConfig(account, app).addHeaderReplacement(regex, replacement);