Update title from 'Comparing query sets' to 'Comparing search configurations' (#11341)

This is not about comparing query sets, but about comparing the results of running the *same* query set in two different search configurations.

Signed-off-by: Stavros Macrakis <[email protected]>

Author: smacrakis

_search-plugins/search-relevance/compare-query-sets.md

@@ -7,7 +7,7 @@ grand_parent: Search relevance
 has_children: false
 ---
 
-# Comparing query sets
+# Comparing search configurations
 
 To compare the results of two different search configurations, you can run a pairwise experiment. To achieve this, you need two search configurations and a query set to use for the search configuration.