message: Add Lunr as example
diff: @@ -26,7 +26,7 @@ Backstage Search isn't a search engine itself, rather, it provides an interface
  between your Backstage instance and a Search Engine of your choice. More
  concretely, a `SearchEngine` is an interface whose concrete implementations
  facilitate communication with different search engines (like ElasticSearch,
  -Solr, etc). This abstraction exists in order to support your organization's
  +Lunr, Solr, etc). This abstraction exists in order to support your organization's
  needs.
  Out of the box, Backstage Search comes pre-packaged with an in-memory search
  