Add rerank link (elastic#1980)

Author: lcawl

explore-analyze/machine-learning/nlp/ml-nlp-built-in-models.md

@@ -13,5 +13,6 @@ products:
 There are {{nlp}} models that are available for use in every cluster out-of-the-box. These models are pre-trained which means they don’t require fine-tuning on your own data, making it adaptable for various use cases out of the box. The following models are available:
 
 * [ELSER](ml-nlp-elser.md) trained by Elastic
+* [](ml-nlp-rerank.md)
 * [E5](ml-nlp-e5.md)
 * [{{lang-ident-cap}}](ml-nlp-lang-ident.md)