[DOCS] Remove 'rescore' from retriever.asciidoc (elastic#116921)

(cherry picked from commit 4e17c61)

# Conflicts:
#	docs/reference/search/retriever.asciidoc

Author: leemthompo

docs/reference/search/retriever.asciidoc

@@ -541,5 +541,4 @@ at the top-level and instead are only allowed as elements of specific retrievers
 * <<search-api-knn, `knn`>>
 * <<search-after, `search_after`>>
 * <<request-body-search-terminate-after, `terminate_after`>>
-* <<search-sort-param, `sort`>>
-* <<rescore, `rescore`>>
+* <<search-sort-param, `sort`>>