Fix typo in stop-tokenfilter.asciidoc (#91128) (#91207)

Since ignore_case is set to true in our custom stop words filter, the matching will be case-insensitive.

(cherry picked from commit a03fba9d77c7ab781fca98eaffe901a17419772e)

Co-authored-by: Siniša Subašić <68671543+sinisuba@users.noreply.github.com>

docs/reference/analysis/tokenfilters/stop-tokenfilter.asciidoc

@@ -203,7 +203,7 @@ PUT /my-index-000001
 ----
 
 You can also specify your own list of stop words. For example, the following
-request creates a custom case-sensitive `stop` filter that removes only the stop
+request creates a custom case-insensitive `stop` filter that removes only the stop
 words `and`, `is`, and `the`:
 
 [source,console]