Update similarity.asciidoc

docs/reference/index-modules/similarity.asciidoc

@@ -157,7 +157,7 @@ implementation used for these two methods, while not changing the
 `default`, it is possible to configure a similarity with the name
 `base`. This similarity will then be used for the two methods.
 
-You can change the default similarity for all fields like this:
+You can change the default similarity for all fields by putting the following setting into `elasticsearch.yml`:
 
 [source,js]
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