Added/updated snippets for docs (#2318)

docs/doc_examples/e891e1d4805172da45a81f62b6b44aca.asciidoc

@@ -0,0 +1,24 @@
+// This file is autogenerated, DO NOT EDIT
+// Use `node scripts/generate-docs-examples.js` to generate the docs examples
+
+[source, js]
+----
+const response = await client.search({
+  size: 0,
+  runtime_mappings: {
+    normalized_genre: {
+      type: "keyword",
+      script:
+        "\n        String genre = doc['genre'].value;\n        if (doc['product'].value.startsWith('Anthology')) {\n          emit(genre + ' anthology');\n        } else {\n          emit(genre);\n        }\n      ",
+    },
+  },
+  aggs: {
+    genres: {
+      terms: {
+        field: "normalized_genre",
+      },
+    },
+  },
+});
+console.log(response);
+----